neutron/neutron/agent/ovn/metadata/server.py

210 lines
7.9 KiB
Python

# Copyright 2017 Red Hat, Inc.
#
# 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 hashlib
import hmac
import urllib
from neutron._i18n import _
from neutron.agent.linux import utils as agent_utils
from neutron.agent.ovn.metadata import ovsdb
from neutron.common import ipv6_utils
from neutron.common.ovn import constants as ovn_const
from neutron.conf.agent.metadata import config
from neutron_lib.callbacks import events
from neutron_lib.callbacks import registry
from neutron_lib.callbacks import resources
from oslo_config import cfg
from oslo_log import log as logging
from oslo_utils import encodeutils
import requests
import webob
LOG = logging.getLogger(__name__)
MODE_MAP = {
config.USER_MODE: 0o644,
config.GROUP_MODE: 0o664,
config.ALL_MODE: 0o666,
}
class MetadataProxyHandler(object):
def __init__(self, conf):
self.conf = conf
self.subscribe()
def subscribe(self):
registry.subscribe(self.post_fork_initialize,
resources.PROCESS,
events.AFTER_INIT)
def post_fork_initialize(self, resource, event, trigger, payload=None):
# We need to open a connection to OVN SouthBound database for
# each worker so that we can process the metadata requests.
self.sb_idl = ovsdb.MetadataAgentOvnSbIdl(
tables=('Port_Binding', 'Datapath_Binding')).start()
@webob.dec.wsgify(RequestClass=webob.Request)
def __call__(self, req):
try:
LOG.debug("Request: %s", req)
instance_id, project_id = self._get_instance_and_project_id(req)
if instance_id:
return self._proxy_request(instance_id, project_id, req)
else:
return webob.exc.HTTPNotFound()
except Exception:
LOG.exception("Unexpected error.")
msg = _('An unknown error has occurred. '
'Please try your request again.')
explanation = str(msg)
return webob.exc.HTTPInternalServerError(explanation=explanation)
def _get_instance_and_project_id(self, req):
remote_address = req.headers.get('X-Forwarded-For')
network_id = req.headers.get('X-OVN-Network-ID')
ports = self.sb_idl.get_network_port_bindings_by_ip(network_id,
remote_address)
num_ports = len(ports)
if num_ports == 1:
external_ids = ports[0].external_ids
return (external_ids[ovn_const.OVN_DEVID_EXT_ID_KEY],
external_ids[ovn_const.OVN_PROJID_EXT_ID_KEY])
elif num_ports == 0:
LOG.error("No port found in network %s with IP address %s",
network_id, remote_address)
elif num_ports > 1:
port_uuids = ', '.join([str(port.uuid) for port in ports])
LOG.error("More than one port found in network %s with IP address "
"%s. Please run the neutron-ovn-db-sync-util script as "
"there seems to be inconsistent data between Neutron "
"and OVN databases. OVN Port uuids: %s", network_id,
remote_address, port_uuids)
return None, None
def _proxy_request(self, instance_id, tenant_id, req):
headers = {
'X-Forwarded-For': req.headers.get('X-Forwarded-For'),
'X-Instance-ID': instance_id,
'X-Tenant-ID': tenant_id,
'X-Instance-ID-Signature': self._sign_instance_id(instance_id)
}
nova_host_port = ipv6_utils.valid_ipv6_url(
self.conf.nova_metadata_host,
self.conf.nova_metadata_port)
url = urllib.parse.urlunsplit((
self.conf.nova_metadata_protocol,
nova_host_port,
req.path_info,
req.query_string,
''))
disable_ssl_certificate_validation = self.conf.nova_metadata_insecure
if self.conf.auth_ca_cert and not disable_ssl_certificate_validation:
verify_cert = self.conf.auth_ca_cert
else:
verify_cert = not disable_ssl_certificate_validation
client_cert = None
if self.conf.nova_client_cert and self.conf.nova_client_priv_key:
client_cert = (self.conf.nova_client_cert,
self.conf.nova_client_priv_key)
resp = requests.request(method=req.method, url=url,
headers=headers,
data=req.body,
cert=client_cert,
verify=verify_cert)
if resp.status_code == 200:
req.response.content_type = resp.headers['content-type']
req.response.body = resp.content
LOG.debug(str(resp))
return req.response
elif resp.status_code == 403:
LOG.warning(
'The remote metadata server responded with Forbidden. This '
'response usually occurs when shared secrets do not match.'
)
return webob.exc.HTTPForbidden()
elif resp.status_code == 400:
return webob.exc.HTTPBadRequest()
elif resp.status_code == 404:
return webob.exc.HTTPNotFound()
elif resp.status_code == 409:
return webob.exc.HTTPConflict()
elif resp.status_code == 500:
msg = _(
'Remote metadata server experienced an internal server error.'
)
LOG.warning(msg)
explanation = str(msg)
return webob.exc.HTTPInternalServerError(explanation=explanation)
else:
raise Exception(_('Unexpected response code: %s') %
resp.status_code)
def _sign_instance_id(self, instance_id):
secret = self.conf.metadata_proxy_shared_secret
secret = encodeutils.to_utf8(secret)
instance_id = encodeutils.to_utf8(instance_id)
return hmac.new(secret, instance_id, hashlib.sha256).hexdigest()
class UnixDomainMetadataProxy(object):
def __init__(self, conf):
self.conf = conf
agent_utils.ensure_directory_exists_without_file(
cfg.CONF.metadata_proxy_socket)
def _get_socket_mode(self):
mode = self.conf.metadata_proxy_socket_mode
if mode == config.DEDUCE_MODE:
user = self.conf.metadata_proxy_user
if (not user or user == '0' or user == 'root' or
agent_utils.is_effective_user(user)):
# user is agent effective user or root => USER_MODE
mode = config.USER_MODE
else:
group = self.conf.metadata_proxy_group
if not group or agent_utils.is_effective_group(group):
# group is agent effective group => GROUP_MODE
mode = config.GROUP_MODE
else:
# otherwise => ALL_MODE
mode = config.ALL_MODE
return MODE_MAP[mode]
def run(self):
self.server = agent_utils.UnixDomainWSGIServer(
'networking-ovn-metadata-agent')
self.server.start(MetadataProxyHandler(self.conf),
self.conf.metadata_proxy_socket,
workers=self.conf.metadata_workers,
backlog=self.conf.metadata_backlog,
mode=self._get_socket_mode())
def wait(self):
self.server.wait()