def _process_good_status(self, single_response, cert_id, ocsp_response):
"""
Process GOOD status
"""
current_time = int(time.time())
this_update_native, next_update_native = \
self.extract_good_status(single_response)
if this_update_native is None or next_update_native is None:
raise OperationalError(
msg=u"Either this update or next "
u"update is None. this_update: {}, next_update: {}".format(
this_update_native, next_update_native),
errno=ER_INVALID_OCSP_RESPONSE)
this_update = (this_update_native.replace(tzinfo=None) -
SnowflakeOCSP.ZERO_EPOCH).total_seconds()
next_update = (next_update_native.replace(tzinfo=None) -
SnowflakeOCSP.ZERO_EPOCH).total_seconds()
if not SnowflakeOCSP._is_validaity_range(current_time, this_update,
next_update):
raise OperationalError(msg=SnowflakeOCSP._validity_error_message(
current_time, this_update, next_update),
errno=ER_INVALID_OCSP_RESPONSE)
SnowflakeOCSP.OCSP_CACHE.update_cache(self, cert_id, ocsp_response)
def _process_good_status(single_response, cert_id, ocsp_response):
"""
Process GOOD status
"""
current_time = int(time.time())
this_update_native = single_response['this_update'].native
next_update_native = single_response['next_update'].native
if this_update_native is None or next_update_native is None:
raise OperationalError(
msg=u"Either this update or next "
u"update is None. this_update: {}, next_update: {}".format(
this_update_native, next_update_native),
errno=ER_INVALID_OCSP_RESPONSE)
this_update = (this_update_native.replace(tzinfo=None) -
ZERO_EPOCH).total_seconds()
next_update = (next_update_native.replace(tzinfo=None) -
ZERO_EPOCH).total_seconds()
if not _is_validaity_range(current_time, this_update, next_update):
raise OperationalError(msg=_validity_error_message(
current_time, this_update, next_update),
errno=ER_INVALID_OCSP_RESPONSE)
with OCSP_VALIDATION_CACHE_LOCK:
hkey = _decode_cert_id_key(cert_id)
if hkey not in OCSP_VALIDATION_CACHE:
OCSP_VALIDATION_CACHE[hkey] = (current_time, ocsp_response)
global OCSP_VALIDATION_CACHE_UPDATED
OCSP_VALIDATION_CACHE_UPDATED = True
def process_ocsp_response(self, issuer, cert_id, ocsp_response):
try:
res = OCSPResponse.load(ocsp_response)
except Exception:
raise OperationalError(msg='Invalid OCSP Response',
errno=ER_INVALID_OCSP_RESPONSE)
if res['response_status'].native != 'successful':
raise OperationalError(msg="Invalid Status: {0}".format(
res['response_status'].native),
errno=ER_INVALID_OCSP_RESPONSE)
basic_ocsp_response = res.basic_ocsp_response
if basic_ocsp_response['certs'].native:
logger.debug("Certificate is attached in Basic OCSP Response")
ocsp_cert = basic_ocsp_response['certs'][0]
logger.debug("Verifying the attached certificate is signed by "
"the issuer")
logger.debug(
"Valid Not After: %s",
ocsp_cert['tbs_certificate']['validity']['not_after'].native)
self.verify_signature(ocsp_cert.hash_algo, ocsp_cert.signature,
issuer, ocsp_cert['tbs_certificate'])
else:
logger.debug("Certificate is NOT attached in Basic OCSP Response. "
"Using issuer's certificate")
ocsp_cert = issuer
tbs_response_data = basic_ocsp_response['tbs_response_data']
logger.debug("Verifying the OCSP response is signed by the issuer.")
self.verify_signature(
basic_ocsp_response['signature_algorithm'].hash_algo,
basic_ocsp_response['signature'].native, ocsp_cert,
tbs_response_data)
single_response = tbs_response_data['responses'][0]
cert_status = single_response['cert_status'].name
if cert_status == 'good':
self._process_good_status(single_response, cert_id, ocsp_response)
SnowflakeOCSP.OCSP_CACHE.update_cache(self, cert_id, ocsp_response)
elif cert_status == 'revoked':
self._process_revoked_status(single_response, cert_id)
elif cert_status == 'unknown':
self._process_unknown_status(cert_id)
else:
raise OperationalError(
msg="Unknown revocation status was returned. OCSP response "
"may be malformed: {0}".format(cert_status),
errno=ER_INVALID_OCSP_RESPONSE_CODE)
def _create_pair_issuer_subject(cert_map):
"""
Creates pairs of issuer and subject certificates
"""
issuer_subject = []
for subject_der in cert_map:
subject = cert_map[subject_der]
if subject.ca and not subject.ocsp_urls:
# Root certificate will not be validated
# but it is used to validate the subject certificate
continue
issuer_hash = subject.issuer.sha256
if issuer_hash not in cert_map:
# IF NO ROOT certificate is attached in the certificate chain
# read it from the local disk
with ROOT_CERTIFICATES_DICT_LOCK:
_lazy_read_ca_bundle()
logger.debug('not found issuer_der: %s', subject.issuer.native)
if issuer_hash not in ROOT_CERTIFICATES_DICT:
raise OperationalError(
msg="CA certificate is NOT found in the root "
"certificate list. Make sure you use the latest "
"Python Connector package and the URL is valid.")
issuer = ROOT_CERTIFICATES_DICT[issuer_hash]
else:
issuer = cert_map[issuer_hash]
issuer_subject.append((issuer, subject))
return issuer_subject
def _fetch_ocsp_response(self, ocsp_request, cert, do_retry=True):
"""
Fetch OCSP response using OCSPRequest
"""
ocsp_url = self.extract_ocsp_url(cert)
if not ocsp_url:
return None
actual_method = 'post' if self._use_post_method else 'get'
if SnowflakeOCSP.OCSP_CACHE.RETRY_URL_PATTERN:
# no POST is supported for Retry URL at the moment.
actual_method = 'get'
if actual_method == 'get':
b64data = self.decode_ocsp_request_b64(ocsp_request)
target_url = SnowflakeOCSP.OCSP_CACHE.generate_get_url(
ocsp_url, b64data)
payload = None
headers = None
else:
target_url = ocsp_url
payload = self.decode_ocsp_request(ocsp_request)
headers = {'Content-Type': 'application/ocsp-request'}
ret = None
logger.debug('url: %s', target_url)
with requests.Session() as session:
session.mount('http://', adapters.HTTPAdapter(max_retries=5))
session.mount('https://', adapters.HTTPAdapter(max_retries=5))
max_retry = 30 if do_retry else 1
sleep_time = 1
backoff = DecorrelateJitterBackoff(sleep_time, 16)
for attempt in range(max_retry):
response = session.request(
headers=headers,
method=actual_method,
url=target_url,
timeout=30,
data=payload,
)
if response.status_code == OK:
logger.debug(
"OCSP response was successfully returned from OCSP "
"server.")
ret = response.content
break
elif max_retry > 1:
sleep_time = backoff.next_sleep(sleep_time)
logger.debug("OCSP server returned %s. Retrying in %s(s)",
response.status_code, sleep_time)
time.sleep(sleep_time)
else:
logger.error("Failed to get OCSP response after %s attempt.",
max_retry)
raise OperationalError(
msg="Failed to get OCSP response after {) attempt.".format(
max_retry),
errno=ER_INVALID_OCSP_RESPONSE)
return ret
def _validate(self, hostname, cert_data, do_retry=True):
global OCSP_VALIDATION_CACHE_UPDATED
global OCSP_VALIDATION_CACHE
global SF_OCSP_RESPONSE_CACHE_SERVER_ENABLED
if SF_OCSP_RESPONSE_CACHE_SERVER_ENABLED:
# Validate certs sequentially if OCSP response cache server is used
results = _validate_certificates_sequential(cert_data, do_retry)
else:
results = _validate_certificates_parallel(cert_data, do_retry)
with OCSP_VALIDATION_CACHE_LOCK:
if OCSP_VALIDATION_CACHE_UPDATED:
update_ocsp_response_cache_file(self._ocsp_response_cache_uri)
OCSP_VALIDATION_CACHE_UPDATED = False
if len(results) != len(cert_data):
raise OperationalError(
msg="Failed to validate the certificate "
"revocation status. The number of validation "
"didn't match: hostname={0}, results={1}, "
"cert_data={2}".format(hostname, len(results), len(cert_data)),
errno=ER_INVALID_OCSP_RESPONSE)
logger.debug('ok')
return True
def _process_unknown_status(self, cert_id):
"""
Process UNKNOWN status
"""
SnowflakeOCSP.OCSP_CACHE.delete_cache(self, cert_id)
raise OperationalError(
msg=u"The certificate is in UNKNOWN revocation status.",
errno=ER_SERVER_CERTIFICATE_UNKNOWN,
)
def _verify_signature(signature_algorithm, signature, cert, data):
rsakey = RSA.importKey(cert.public_key.unwrap().dump())
signer = PKCS1_v1_5.new(rsakey)
if signature_algorithm in SIGNATURE_ALGORITHM_TO_DIGEST_CLASS:
digest = SIGNATURE_ALGORITHM_TO_DIGEST_CLASS[signature_algorithm].new()
else:
# the last resort. should not happen.
digest = SHA1.new()
digest.update(data.dump())
if not signer.verify(digest, signature):
raise OperationalError(msg="Failed to verify the signature",
errno=ER_INVALID_OCSP_RESPONSE)
def _process_unknown_status(cert_id):
"""
Process UNKNOWN status
"""
with OCSP_VALIDATION_CACHE_LOCK:
hkey = _decode_cert_id_key(cert_id)
if hkey in OCSP_VALIDATION_CACHE:
global OCSP_VALIDATION_CACHE_UPDATED
OCSP_VALIDATION_CACHE_UPDATED = True
del OCSP_VALIDATION_CACHE[hkey]
raise OperationalError(
msg=u"The certificate is in UNKNOWN revocation status.",
errno=ER_SERVER_CERTIFICATE_REVOKED,
)
def _fetch_ocsp_response(req, cert, do_retry=True):
"""
Fetch OCSP response using OCSPRequest
"""
global SF_OCSP_RESPONSE_CACHE_SERVER_RETRY_URL_PATTERN
max_retry = 100 if do_retry else 1
data = req.dump() # convert to DER
b64data = b64encode(data).decode('ascii')
urls = cert.ocsp_urls
ocsp_url = urls[0]
if SF_OCSP_RESPONSE_CACHE_SERVER_RETRY_URL_PATTERN:
parsed_url = urlsplit(ocsp_url)
target_url = SF_OCSP_RESPONSE_CACHE_SERVER_RETRY_URL_PATTERN.format(
parsed_url.hostname, b64data
)
else:
target_url = u"{0}/{1}".format(ocsp_url, b64data)
ret = None
logger.debug('url: %s', target_url)
with requests.Session() as session:
session.mount('http://', adapters.HTTPAdapter(max_retries=5))
session.mount('https://', adapters.HTTPAdapter(max_retries=5))
global PROXIES
for attempt in range(max_retry):
response = session.get(
target_url,
proxies=PROXIES,
timeout=30)
if response.status_code == OK:
logger.debug(
"OCSP response was successfully returned from OCSP server.")
ret = response.content
break
elif max_retry > 1:
wait_time = 2 ** attempt
wait_time = 16 if wait_time > 16 else wait_time
logger.debug("OCSP server returned %s. Retrying in %s(s)",
response.status_code, wait_time)
time.sleep(wait_time)
else:
logger.error("Failed to get OCSP response after %s attempt.",
max_retry)
raise OperationalError(
msg="Failed to get OCSP response after {) attempt.".format(
max_retry),
errno=ER_INVALID_OCSP_RESPONSE
)
return ret
def _process_revoked_status(self, single_response, cert_id):
"""
Process REVOKED status
"""
current_time = int(time.time())
SnowflakeOCSP.OCSP_CACHE.delete_cache(self, cert_id)
revocation_time, revocation_reason = self.extract_revoked_status(
single_response)
raise OperationalError(
msg="The certificate has been revoked: current_time={0}, "
"revocation_time={1}, reason={2}".format(
strftime(SnowflakeOCSP.OUTPUT_TIMESTAMP_FORMAT,
gmtime(current_time)),
revocation_time.strftime(
SnowflakeOCSP.OUTPUT_TIMESTAMP_FORMAT), revocation_reason),
errno=ER_SERVER_CERTIFICATE_REVOKED)
def _fetch_ocsp_response(req, cert, do_retry=True):
"""
Fetch OCSP response using OCSPRequest
"""
urls = cert.ocsp_urls
parsed_url = urlsplit(urls[0]) # urls is guaranteed to have OCSP URL
max_retry = 100 if do_retry else 1
data = req.dump() # convert to DER
headers = {
'Content-Type': 'application/ocsp-request',
'Content-Length': '{0}'.format(len(data)),
'Host': parsed_url.hostname,
}
ret = None
with requests.Session() as session:
session.mount('http://', adapters.HTTPAdapter(max_retries=5))
session.mount('https://', adapters.HTTPAdapter(max_retries=5))
global PROXIES
for attempt in range(max_retry):
response = session.post(urls[0],
headers=headers,
proxies=PROXIES,
data=data,
timeout=30)
if response.status_code == OK:
logger.debug("OCSP response was successfully returned from "
"OCSP server.")
ret = response.content
break
elif max_retry > 1:
wait_time = 2**attempt
wait_time = 16 if wait_time > 16 else wait_time
logger.debug("OCSP server returned %s. Retrying in %s(s)",
response.status_code, wait_time)
time.sleep(wait_time)
else:
logger.error("Failed to get OCSP response after %s attempt.",
max_retry)
raise OperationalError(
msg="Failed to get OCSP response after {) attempt.".format(
max_retry),
errno=ER_INVALID_OCSP_RESPONSE)
return ret
def _validate_certificates_parallel(cert_data, do_retry=True):
pool = ThreadPool(len(cert_data))
results = []
try:
_check_ocsp_response_cacher_ser(cert_data)
for issuer, subject in cert_data:
r = pool.apply_async(validate_by_direct_connection,
[issuer, subject, do_retry])
results.append(r)
finally:
pool.close()
pool.join()
for r in results:
if not r.successful():
raise OperationalError(
msg="Failed to validate the certificate "
"revocation status: err={0}".format(r.get()))
return results
def _process_revoked_status(single_response, cert_id):
"""
Process REVOKED status
"""
current_time = int(time.time())
with OCSP_VALIDATION_CACHE_LOCK:
hkey = _decode_cert_id_key(cert_id)
if hkey in OCSP_VALIDATION_CACHE:
del OCSP_VALIDATION_CACHE[hkey]
global OCSP_VALIDATION_CACHE_UPDATED
OCSP_VALIDATION_CACHE_UPDATED = True
revoked_info = single_response['cert_status']
revocation_time = revoked_info.native['revocation_time']
revocation_reason = revoked_info.native['revocation_reason']
raise OperationalError(
msg="The certificate has been revoked: current_time={0}, "
"revocation_time={1}, reason={2}".format(
strftime(OUTPUT_TIMESTAMP_FORMAT, gmtime(current_time)),
revocation_time.strftime(OUTPUT_TIMESTAMP_FORMAT),
revocation_reason),
errno=ER_SERVER_CERTIFICATE_REVOKED)
def is_valid_time(self, cert_id, ocsp_response):
res = OCSPResponse.load(ocsp_response)
if res['response_status'].native != 'successful':
raise OperationalError(msg="Invalid Status: {0}".format(
res['response_status'].native),
errno=ER_INVALID_OCSP_RESPONSE)
basic_ocsp_response = res.basic_ocsp_response
tbs_response_data = basic_ocsp_response['tbs_response_data']
single_response = tbs_response_data['responses'][0]
cert_status = single_response['cert_status'].name
try:
if cert_status == 'good':
self._process_good_status(single_response, cert_id,
ocsp_response)
except Exception as ex:
logger.debug("Failed to validate ocsp response %s", ex)
return False
return True