authority.v2: Add ACMEv2 API implementation

This commit is contained in:
Kishi85 2019-03-18 20:58:30 +01:00
parent d272f9ada3
commit 530256ecec
2 changed files with 265 additions and 0 deletions

262
acertmgr/authority/v2.py Normal file
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@ -0,0 +1,262 @@
#!/usr/bin/env python
# -*- coding: utf-8 -*-
# acertmgr - acme api v2 functions
# Copyright (c) Rudolf Mayerhofer, 2019.
# available under the ISC license, see LICENSE
import copy
import datetime
import json
import re
import time
from cryptography import x509
from cryptography.hazmat.backends import default_backend
from cryptography.hazmat.primitives import hashes, serialization
from cryptography.hazmat.primitives.asymmetric import padding
from acertmgr import tools
from acertmgr.authority.acme import ACMEAuthority as AbstractACMEAuthority
from acertmgr.tools import byte_string_format
try:
from urllib.request import urlopen, Request # Python 3
except ImportError:
from urllib2 import urlopen, Request # Python 2
class ACMEAuthority(AbstractACMEAuthority):
# @brief Init class with config
# @param config Configuration data
# @param key Account key data
def __init__(self, config, key):
AbstractACMEAuthority.__init__(self, config, key)
# Initialize config vars
self.ca = config['authority']
self.agreement = str(config.get('authority_agreement')) == 'true'
contact_email = config.get('authority_contact_email')
if contact_email is None:
self.contact = None
elif isinstance(contact_email, list):
self.contact = ["mailto:{}".format(contact) for contact in contact_email]
else:
self.contact = ["mailto:{}".format(contact_email)]
# Initialize runtime vars
_, self.directory, _ = self._request_url(self.ca + '/directory')
self._request_endpoint('newNonce') # cache the first nonce
# @todo: Add support for key-types other than RSA
numbers = key.public_key().public_numbers()
self.algorithm = "RS256"
self.account_protected = {
"alg": self.algorithm,
"jwk": {
"kty": "RSA",
"e": tools.to_json_base64(byte_string_format(numbers.e)),
"n": tools.to_json_base64(byte_string_format(numbers.n)),
},
}
self.account_id = None # will be updated to correct value during account registration
# @brief fetch a given url
def _request_url(self, url, data=None, raw_result=False):
header = {'Content-Type': 'application/jose+json'}
if data:
data = data.encode('utf-8')
resp = urlopen(Request(url, data=data, headers=header))
if raw_result:
return resp.getcode(), resp.read(), resp.headers
body = resp.read()
if len(body) > 0:
try:
body = json.loads(body.decode('utf-8'))
except json.JSONDecodeError as e:
raise ValueError('Could not parse non-raw result (expected JSON)', e)
# Store next Replay-Nonce if it is in the header
if 'Replay-Nonce' in resp.headers:
self.nonce = resp.headers['Replay-Nonce']
return resp.getcode(), body, resp.headers
# @brief helper function to make signed requests
def _request_acme_url(self, url, payload=None, protected=None, raw_result=False):
if not payload:
payload = {}
if not protected:
protected = {}
payload64 = tools.to_json_base64(json.dumps(payload).encode('utf8'))
# Request a new nonce if there is none in cache
if not self.nonce:
self._request_endpoint('newNonce')
protected["nonce"] = self.nonce
protected["url"] = url
if self.algorithm:
protected["alg"] = self.algorithm
if self.account_id:
protected["kid"] = self.account_id
protected64 = tools.to_json_base64(json.dumps(protected).encode('utf8'))
pad = padding.PKCS1v15()
out = self.key.sign('.'.join([protected64, payload64]).encode('utf8'), pad, hashes.SHA256())
data = json.dumps({
"protected": protected64,
"payload": payload64,
"signature": tools.to_json_base64(out),
})
try:
return self._request_url(url, data, raw_result)
except IOError as e:
return getattr(e, "code", None), getattr(e, "read", e.__str__)(), {}
finally:
# Dispose of nonce after it was used
self.nonce = None
# @brief send a request to authority
def _request_endpoint(self, request, data=None, raw_result=False):
return self._request_url(self.directory[request], data, raw_result)
# @brief send a signed request to authority
def _request_acme_endpoint(self, request, payload=None, protected=None, raw_result=False):
return self._request_acme_url(self.directory[request], payload, protected, raw_result)
# @brief register an account over ACME
def register_account(self):
protected = copy.deepcopy(self.account_protected)
payload = {
"termsOfServiceAgreed": self.agreement,
"onlyReturnExisting": False,
}
if self.contact:
payload["contact"] = self.contact
code, result, headers = self._request_acme_endpoint("newAccount", payload, protected)
if code < 400 and result['status'] == 'valid':
self.account_id = headers['Location']
if 'meta' in self.directory and 'termsOfService' in self.directory['meta']:
print("ToS at {} have been accepted.".format(self.directory['meta']['termsOfService']))
print("Account registered and valid.".format())
else:
raise ValueError("Error registering account: {0} {1}".format(code, result))
# @brief function to fetch certificate using ACME
# @param csr the certificate signing request in pyopenssl format
# @param domains list of domains in the certificate, first is CN
# @param challenge_handlers a dict containing challenge for all given domains
# @return the certificate
# @note algorithm and parts of the code are from acme-tiny
def get_crt_from_csr(self, csr, domains, challenge_handlers):
accountkey_json = json.dumps(self.account_protected['jwk'], sort_keys=True, separators=(',', ':'))
account_hash = hashes.Hash(hashes.SHA256(), backend=default_backend())
account_hash.update(accountkey_json.encode('utf8'))
account_thumbprint = tools.to_json_base64(account_hash.finalize())
print("Ordering certificate for {}".format(domains))
identifiers = [{'type': 'dns', 'value': domain} for domain in domains]
code, order, headers = self._request_acme_endpoint('newOrder', {'identifiers': identifiers})
if code >= 400:
raise ValueError("Error with certificate order: {0} {1}".format(code, order))
order_url = headers['Location']
authorizations = list()
# verify each domain
try:
valid_times = list()
for authorizationUrl in order['authorizations']:
# get new challenge
code, authorization, _ = self._request_url(authorizationUrl)
if code >= 400:
raise ValueError("Error requesting authorization: {0} {1}".format(code, authorization))
authorization['_domain'] = \
"*.{}".format(authorization['identifier']['value']) \
if 'wildcard' in authorization and authorization['wildcard'] \
else authorization['identifier']['value']
print("Authorizing {0}".format(authorization['_domain']))
# create the challenge
matching_challenges = [c for c in authorization['challenges'] if
c['type'] == challenge_handlers[authorization['_domain']].get_challenge_type()]
if len(matching_challenges) == 0:
raise ValueError("Error no challenge matching {0} found: {1}".format(
challenge_handlers[authorization['_domain']].get_challenge_type(), authorization))
authorization['_challenge'] = matching_challenges[0]
authorization['_token'] = re.sub(r"[^A-Za-z0-9_\-]", "_", authorization['_challenge']['token'])
if authorization['_domain'] not in challenge_handlers:
raise ValueError("No challenge handler given for domain: {0}".format(authorization['_domain']))
valid_times.append(
challenge_handlers[authorization['_domain']].create_challenge(authorization['identifier']['value'],
account_thumbprint,
authorization['_token']))
authorizations.append(authorization)
print("Waiting until challenges are valid ({})".format(",".join([str(x) for x in valid_times])))
for valid_time in valid_times:
while datetime.datetime.now() < valid_time:
time.sleep(1)
for authorization in authorizations:
print("Starting verification of {}".format(authorization['_domain']))
challenge_handlers[authorization['_domain']].start_challenge()
try:
# notify challenge is met
code, challenge_status, _ = self._request_acme_url(authorization['_challenge']['url'], {
"keyAuthorization": "{0}.{1}".format(authorization['_token'], account_thumbprint),
})
# wait for challenge to be verified
while code < 400 and challenge_status.get('status') == "pending":
time.sleep(5)
code, challenge_status, _ = self._request_url(authorization['_challenge']['url'])
if challenge_status.get('status') == "valid":
print("{0} verified".format(authorization['_domain']))
else:
raise ValueError("{0} challenge did not pass: {1}".format(
authorization['_domain'], challenge_status))
finally:
challenge_handlers[authorization['_domain']].stop_challenge()
finally:
# Destroy challenge handlers in reverse order to replay
# any saved state information in the handlers correctly
for authorization in reversed(authorizations):
try:
challenge_handlers[authorization['_domain']].destroy_challenge(
authorization['identifier']['value'], account_thumbprint, authorization['_token'])
except (KeyboardInterrupt, SystemError, SystemExit):
# Re-raise runtime/system exceptions
raise
except:
pass
# check order status and retry once
code, order, _ = self._request_url(order_url)
if code < 400 and order.get('status') == 'pending':
time.sleep(5)
code, order, _ = self._request_url(order_url)
if code >= 400:
raise ValueError("Order is still pending: {0} {1}".format(code, order))
# get the new certificate
print("Finalizing certificate")
csr_der = csr.public_bytes(serialization.Encoding.DER)
code, finalize, _ = self._request_acme_url(order['finalize'], {
"csr": tools.to_json_base64(csr_der),
})
while code < 400 and (finalize.get('status') == 'pending' or finalize.get('status') == 'processing'):
time.sleep(5)
code, finalize, _ = self._request_url(order_url)
if code >= 400:
raise ValueError("Error finalizing certificate: {0} {1}".format(code, finalize))
print("Certificate ready!")
# return certificate
code, certificate, _ = self._request_url(finalize['certificate'], raw_result=True)
if code >= 400:
raise ValueError("Error downloading certificate: {0} {1}".format(code, certificate))
cert = x509.load_pem_x509_certificate(certificate, default_backend())
return cert

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@ -74,6 +74,9 @@ def parse_config_entry(entry, globalconfig, work_dir):
# Certificate authority agreement
update_config_value(config, 'authority_agreement', entry, globalconfig, DEFAULT_AUTHORITY_AGREEMENT)
# Certificate authority contact email addresses
update_config_value(config, 'authority_contact_email', entry, globalconfig, None)
# Account key
update_config_value(config, 'account_key', entry, globalconfig, os.path.join(work_dir, "account.key"))