lemur/lemur/plugins/lemur_acme/challenge_types.py

264 lines
11 KiB
Python

"""
.. module: lemur.plugins.lemur_acme.plugin
:platform: Unix
:synopsis: This module contains the different challenge types for ACME implementations
:copyright: (c) 2018 by Netflix Inc., see AUTHORS for more
:license: Apache, see LICENSE for more details.
.. moduleauthor:: Mathias Petermann <mathias.petermann@projektfokus.ch>
"""
import datetime
import json
from acme import challenges
from acme.messages import errors, STATUS_VALID, ERROR_CODES
from flask import current_app
from lemur.authorizations import service as authorization_service
from lemur.exceptions import LemurException, InvalidConfiguration
from lemur.plugins.base import plugins
from lemur.destinations import service as destination_service
from lemur.plugins.lemur_acme.acme_handlers import AcmeHandler, AcmeDnsHandler
class AcmeChallengeMissmatchError(LemurException):
pass
class AcmeChallenge(object):
"""
This is the base class, all ACME challenges will need to extend, allowing for future extendability
"""
def create_certificate(self, csr, issuer_options):
"""
Create the new certificate, using the provided CSR and issuer_options.
Right now this is basically a copy of the create_certificate methods in the AcmeHandlers, but should be cleaned
and tried to make use of the deploy and cleanup methods
:param csr:
:param issuer_options:
:return:
"""
pass
def deploy(self, challenge, acme_client, validation_target):
"""
In here the challenge validation is fetched and deployed somewhere that it can be validated by the provider
:param self:
:param challenge: the challenge object, must match for the challenge implementation
:param acme_client: an already bootstrapped acme_client, to avoid passing all issuer_options and so on
:param validation_target: an identifier for the validation target, e.g. the name of a DNS provider
"""
raise NotImplementedError
def cleanup(self, challenge, acme_client, validation_target):
"""
Ideally the challenge should be cleaned up, after the validation is done
:param challenge: Needed to identify the challenge to be removed
:param acme_client: an already bootstrapped acme_client, to avoid passing all issuer_options and so on
:param validation_target: Needed to remove the validation
"""
raise NotImplementedError
class AcmeHttpChallenge(AcmeChallenge):
challengeType = challenges.HTTP01
def create_certificate(self, csr, issuer_options):
"""
Creates an ACME certificate using the HTTP-01 challenge.
:param csr:
:param issuer_options:
:return: :raise Exception:
"""
self.acme = AcmeHandler()
authority = issuer_options.get("authority")
acme_client, registration = self.acme.setup_acme_client(authority)
orderr = acme_client.new_order(csr)
chall = []
deployed_challenges = []
all_pre_validated = True
for authz in orderr.authorizations:
# Choosing challenge.
# check if authorizations is already in a valid state
if authz.body.status != STATUS_VALID:
all_pre_validated = False
# authz.body.challenges is a set of ChallengeBody objects.
for i in authz.body.challenges:
# Find the supported challenge.
if isinstance(i.chall, challenges.HTTP01):
chall.append(i)
else:
current_app.logger.info("{} already validated, skipping".format(authz.body.identifier.value))
if len(chall) == 0 and not all_pre_validated:
raise Exception('HTTP-01 challenge was not offered by the CA server at {}'.format(orderr.uri))
elif not all_pre_validated:
validation_target = None
for option in json.loads(issuer_options["authority"].options):
if option["name"] == "tokenDestination":
validation_target = option["value"]
if validation_target is None:
raise Exception('No token_destination configured for this authority. Cant complete HTTP-01 challenge')
for challenge in chall:
try:
response = self.deploy(challenge, acme_client, validation_target)
deployed_challenges.append(challenge.chall.path)
acme_client.answer_challenge(challenge, response)
except Exception as e:
current_app.logger.error(e)
raise Exception('Failure while trying to deploy token to configure destination. See logs for more information')
current_app.logger.info("Uploaded HTTP-01 challenge tokens, trying to poll and finalize the order")
try:
deadline = datetime.datetime.now() + datetime.timedelta(seconds=90)
orderr = acme_client.poll_authorizations(orderr, deadline)
finalized_orderr = acme_client.finalize_order(orderr, deadline, fetch_alternative_chains=True)
except errors.ValidationError as validationError:
for authz in validationError.failed_authzrs:
for chall in authz.body.challenges:
if chall.error:
current_app.logger.error(
"ValidationError occured of type {}, with message {}".format(chall.error.typ,
ERROR_CODES[chall.error.code]))
raise Exception('Validation error occured, can\'t complete challenges. See logs for more information.')
pem_certificate, pem_certificate_chain = self.acme.extract_cert_and_chain(finalized_orderr.fullchain_pem,
finalized_orderr.alternative_fullchains_pem)
if len(deployed_challenges) != 0:
for token_path in deployed_challenges:
self.cleanup(token_path, validation_target)
# validation is a random string, we use it as external id, to make it possible to implement revoke_certificate
return pem_certificate, pem_certificate_chain, None
def deploy(self, challenge, acme_client, validation_target):
if not isinstance(challenge.chall, challenges.HTTP01):
raise AcmeChallengeMissmatchError(
'The provided challenge is not of type HTTP01, but instead of type {}'.format(
challenge.__class__.__name__))
destination = destination_service.get(validation_target)
if destination is None:
raise Exception(
'Couldn\'t find the destination with name {}. Cant complete HTTP01 challenge'.format(validation_target))
destination_plugin = plugins.get(destination.plugin_name)
response, validation = challenge.response_and_validation(acme_client.net.key)
destination_plugin.upload_acme_token(challenge.chall.path, validation, destination.options)
current_app.logger.info("Uploaded HTTP-01 challenge token.")
return response
def cleanup(self, token_path, validation_target):
destination = destination_service.get(validation_target)
if destination is None:
current_app.logger.info(
'Couldn\'t find the destination with name {}, won\'t cleanup the challenge'.format(validation_target))
destination_plugin = plugins.get(destination.plugin_name)
destination_plugin.delete_acme_token(token_path, destination.options)
current_app.logger.info("Cleaned up HTTP-01 challenge token.")
class AcmeDnsChallenge(AcmeChallenge):
challengeType = challenges.DNS01
def create_certificate(self, csr, issuer_options):
"""
Creates an ACME certificate.
:param csr:
:param issuer_options:
:return: :raise Exception:
"""
self.acme = AcmeDnsHandler()
authority = issuer_options.get("authority")
create_immediately = issuer_options.get("create_immediately", False)
acme_client, registration = self.acme.setup_acme_client(authority)
dns_provider = issuer_options.get("dns_provider", {})
if dns_provider:
dns_provider_options = dns_provider.options
credentials = json.loads(dns_provider.credentials)
current_app.logger.debug(
"Using DNS provider: {0}".format(dns_provider.provider_type)
)
dns_provider_plugin = __import__(
dns_provider.provider_type, globals(), locals(), [], 1
)
account_number = credentials.get("account_id")
provider_type = dns_provider.provider_type
if provider_type == "route53" and not account_number:
error = "Route53 DNS Provider {} does not have an account number configured.".format(
dns_provider.name
)
current_app.logger.error(error)
raise InvalidConfiguration(error)
else:
dns_provider = {}
dns_provider_options = None
account_number = None
provider_type = None
domains = self.acme.get_domains(issuer_options)
if not create_immediately:
# Create pending authorizations that we'll need to do the creation
dns_authorization = authorization_service.create(
account_number, domains, provider_type
)
# Return id of the DNS Authorization
return None, None, dns_authorization.id
authorizations = self.acme.get_authorizations(
acme_client,
account_number,
domains,
dns_provider_plugin,
dns_provider_options,
)
self.acme.finalize_authorizations(
acme_client,
account_number,
dns_provider_plugin,
authorizations,
dns_provider_options,
)
pem_certificate, pem_certificate_chain = self.acme.request_certificate(
acme_client, authorizations, csr
)
# TODO add external ID (if possible)
return pem_certificate, pem_certificate_chain, None
def deploy(self, challenge, acme_client, validation_target):
pass
def cleanup(self, authorizations, acme_client, validation_target):
"""
Best effort attempt to delete DNS challenges that may not have been deleted previously. This is usually called
on an exception
:param authorizations: all the authorizations to be cleaned up
:param acme_client: an already bootstrapped acme_client, to avoid passing all issuer_options and so on
:param validation_target: Unused right now
:return:
"""
acme = AcmeDnsHandler()
acme.cleanup_dns_challenges(acme_client, authorizations)