cloudbase-init/cloudbaseinit/plugins/common/userdata.py

201 lines
8.0 KiB
Python

# Copyright 2012 Cloudbase Solutions Srl
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
import email
import os
from oslo_log import log as oslo_logging
from cloudbaseinit import conf as cloudbaseinit_conf
from cloudbaseinit import exception
from cloudbaseinit.metadata.services import base as metadata_services_base
from cloudbaseinit.osutils import factory as osutils_factory
from cloudbaseinit.plugins.common import base
from cloudbaseinit.plugins.common import execcmd
from cloudbaseinit.plugins.common.userdataplugins import factory
from cloudbaseinit.plugins.common import userdatautils
from cloudbaseinit.utils import encoding
from cloudbaseinit.utils import x509constants
CONF = cloudbaseinit_conf.CONF
LOG = oslo_logging.getLogger(__name__)
class UserDataPlugin(base.BasePlugin):
_PART_HANDLER_CONTENT_TYPE = "text/part-handler"
_GZIP_MAGIC_NUMBER = b'\x1f\x8b'
def execute(self, service, shared_data):
try:
user_data = service.get_decoded_user_data()
except metadata_services_base.NotExistingMetadataException:
return base.PLUGIN_EXECUTION_DONE, False
if not user_data:
return base.PLUGIN_EXECUTION_DONE, False
LOG.debug('User data content length: %d' % len(user_data))
if CONF.userdata_save_path:
user_data_path = os.path.abspath(
os.path.expandvars(CONF.userdata_save_path))
self._write_userdata(user_data, user_data_path)
if CONF.process_userdata:
return self._process_user_data(user_data)
return base.PLUGIN_EXECUTION_DONE, False
@staticmethod
def _write_userdata(user_data, user_data_path):
dir_path = os.path.dirname(user_data_path)
if not os.path.exists(dir_path):
os.makedirs(dir_path)
elif not os.path.isdir(dir_path):
raise exception.CloudbaseInitException(
'Path "%s" exists but it is not a directory' % dir_path)
osutils = osutils_factory.get_os_utils()
osutils.set_path_admin_acls(dir_path)
if os.path.exists(user_data_path):
osutils.take_path_ownership(user_data_path)
os.unlink(user_data_path)
LOG.debug("Writing userdata to: %s", user_data_path)
with open(user_data_path, 'wb') as file:
file.write(user_data)
@staticmethod
def _parse_mime(user_data):
user_data_str = encoding.get_as_string(user_data)
LOG.debug('User data content:\n%s', user_data_str)
return email.message_from_string(user_data_str).walk()
@staticmethod
def _get_headers(user_data):
"""Returns the header of the given user data.
:param user_data: Represents the content of the user data.
:rtype: A string chunk containing the header or None.
.. note :: In case the content type is not valid,
None will be returned.
"""
content = encoding.get_as_string(user_data)
if content:
return content.split("\n\n")[0]
else:
raise exception.CloudbaseInitException("No header could be found."
"The user data content is "
"either invalid or empty.")
def _process_user_data(self, user_data):
plugin_status = base.PLUGIN_EXECUTION_DONE
reboot = False
headers = self._get_headers(user_data)
if 'Content-Type: multipart' in headers:
LOG.debug("Processing userdata")
user_data_plugins = factory.load_plugins()
user_handlers = {}
for part in self._parse_mime(user_data):
(plugin_status, reboot) = self._process_part(part,
user_data_plugins,
user_handlers)
if reboot:
break
if not reboot:
for handler_func in list(set(user_handlers.values())):
self._end_part_process_event(handler_func)
return plugin_status, reboot
else:
return self._process_non_multi_part(user_data)
def _process_part(self, part, user_data_plugins, user_handlers):
ret_val = None
try:
content_type = part.get_content_type()
handler_func = user_handlers.get(content_type)
if handler_func:
LOG.debug("Calling user part handler for content type: %s" %
content_type)
handler_func(None, content_type, part.get_filename(),
part.get_payload(decode=True))
else:
user_data_plugin = user_data_plugins.get(content_type)
if not user_data_plugin:
LOG.info("Userdata plugin not found for content type: %s" %
content_type)
else:
LOG.debug("Executing userdata plugin: %s" %
user_data_plugin.__class__.__name__)
if content_type == self._PART_HANDLER_CONTENT_TYPE:
new_user_handlers = user_data_plugin.process(part)
self._add_part_handlers(user_data_plugins,
user_handlers,
new_user_handlers)
else:
ret_val = user_data_plugin.process(part)
except Exception as ex:
LOG.error('Exception during multipart part handling: '
'%(content_type)s, %(filename)s' %
{'content_type': part.get_content_type(),
'filename': part.get_filename()})
LOG.exception(ex)
return execcmd.get_plugin_return_value(ret_val)
def _add_part_handlers(self, user_data_plugins, user_handlers,
new_user_handlers):
handler_funcs = set()
for (content_type,
handler_func) in new_user_handlers.items():
if not user_data_plugins.get(content_type):
LOG.info("Adding part handler for content "
"type: %s" % content_type)
user_handlers[content_type] = handler_func
handler_funcs.add(handler_func)
else:
LOG.info("Skipping part handler for content type \"%s\" as it "
"is already managed by a plugin" % content_type)
for handler_func in handler_funcs:
self._begin_part_process_event(handler_func)
def _begin_part_process_event(self, handler_func):
LOG.debug("Calling part handler \"__begin__\" event")
handler_func(None, "__begin__", None, None)
def _end_part_process_event(self, handler_func):
LOG.debug("Calling part handler \"__end__\" event")
handler_func(None, "__end__", None, None)
def _process_non_multi_part(self, user_data):
ret_val = None
if user_data.startswith(b'#cloud-config'):
user_data_plugins = factory.load_plugins()
cloud_config_plugin = user_data_plugins.get('text/cloud-config')
ret_val = cloud_config_plugin.process_non_multipart(user_data)
elif user_data.strip().startswith(x509constants.PEM_HEADER.encode()):
LOG.debug('Found X509 certificate in userdata')
else:
ret_val = userdatautils.execute_user_data_script(user_data)
return execcmd.get_plugin_return_value(ret_val)