# vim: tabstop=4 shiftwidth=4 softtabstop=4 # # Copyright 2012 New Dream Network, LLC (DreamHost) # # 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. # # @author: Mark McClain, DreamHost import hashlib import hmac import os import socket import urlparse import eventlet import httplib2 from neutronclient.v2_0 import client from oslo.config import cfg import webob from neutron.common import config from neutron.common import utils from neutron.openstack.common import log as logging from neutron import wsgi LOG = logging.getLogger(__name__) DEVICE_OWNER_ROUTER_INTF = "network:router_interface" class MetadataProxyHandler(object): OPTS = [ cfg.StrOpt('admin_user', help=_("Admin user")), cfg.StrOpt('admin_password', help=_("Admin password"), secret=True), cfg.StrOpt('admin_tenant_name', help=_("Admin tenant name")), cfg.StrOpt('auth_url', help=_("Authentication URL")), cfg.StrOpt('auth_strategy', default='keystone', help=_("The type of authentication to use")), cfg.StrOpt('auth_region', help=_("Authentication region")), cfg.StrOpt('endpoint_type', default='adminURL', help=_("Network service endpoint type to pull from " "the keystone catalog")), cfg.StrOpt('nova_metadata_ip', default='127.0.0.1', help=_("IP address used by Nova metadata server.")), cfg.IntOpt('nova_metadata_port', default=8775, help=_("TCP Port used by Nova metadata server.")), cfg.StrOpt('metadata_proxy_shared_secret', default='', help=_('Shared secret to sign instance-id request'), secret=True) ] def __init__(self, conf): self.conf = conf self.auth_info = {} def _get_neutron_client(self): qclient = client.Client( username=self.conf.admin_user, password=self.conf.admin_password, tenant_name=self.conf.admin_tenant_name, auth_url=self.conf.auth_url, auth_strategy=self.conf.auth_strategy, region_name=self.conf.auth_region, auth_token=self.auth_info.get('auth_token'), endpoint_url=self.auth_info.get('endpoint_url'), endpoint_type=self.conf.endpoint_type ) return qclient @webob.dec.wsgify(RequestClass=webob.Request) def __call__(self, req): try: LOG.debug(_("Request: %s"), req) instance_id = self._get_instance_id(req) if instance_id: return self._proxy_request(instance_id, req) else: return webob.exc.HTTPNotFound() except Exception: LOG.exception(_("Unexpected error.")) msg = _('An unknown error has occurred. ' 'Please try your request again.') return webob.exc.HTTPInternalServerError(explanation=unicode(msg)) def _get_instance_id(self, req): qclient = self._get_neutron_client() remote_address = req.headers.get('X-Forwarded-For') network_id = req.headers.get('X-Neutron-Network-ID') router_id = req.headers.get('X-Neutron-Router-ID') if network_id: networks = [network_id] else: internal_ports = qclient.list_ports( device_id=router_id, device_owner=DEVICE_OWNER_ROUTER_INTF)['ports'] networks = [p['network_id'] for p in internal_ports] ports = qclient.list_ports( network_id=networks, fixed_ips=['ip_address=%s' % remote_address])['ports'] self.auth_info = qclient.get_auth_info() if len(ports) == 1: return ports[0]['device_id'] def _proxy_request(self, instance_id, req): headers = { 'X-Forwarded-For': req.headers.get('X-Forwarded-For'), 'X-Instance-ID': instance_id, 'X-Instance-ID-Signature': self._sign_instance_id(instance_id) } url = urlparse.urlunsplit(( 'http', '%s:%s' % (self.conf.nova_metadata_ip, self.conf.nova_metadata_port), req.path_info, req.query_string, '')) h = httplib2.Http() resp, content = h.request(url, method=req.method, headers=headers, body=req.body) if resp.status == 200: LOG.debug(str(resp)) return content elif resp.status == 403: msg = _( 'The remote metadata server responded with Forbidden. This ' 'response usually occurs when shared secrets do not match.' ) LOG.warn(msg) return webob.exc.HTTPForbidden() elif resp.status == 404: return webob.exc.HTTPNotFound() elif resp.status == 409: return webob.exc.HTTPConflict() elif resp.status == 500: msg = _( 'Remote metadata server experienced an internal server error.' ) LOG.warn(msg) return webob.exc.HTTPInternalServerError(explanation=unicode(msg)) else: raise Exception(_('Unexpected response code: %s') % resp.status) def _sign_instance_id(self, instance_id): return hmac.new(self.conf.metadata_proxy_shared_secret, instance_id, hashlib.sha256).hexdigest() class UnixDomainHttpProtocol(eventlet.wsgi.HttpProtocol): def __init__(self, request, client_address, server): if client_address == '': client_address = ('', 0) # base class is old-style, so super does not work properly eventlet.wsgi.HttpProtocol.__init__(self, request, client_address, server) class UnixDomainWSGIServer(wsgi.Server): def start(self, application, file_socket, backlog=128): sock = eventlet.listen(file_socket, family=socket.AF_UNIX, backlog=backlog) self.pool.spawn_n(self._run, application, sock) def _run(self, application, socket): """Start a WSGI service in a new green thread.""" logger = logging.getLogger('eventlet.wsgi.server') eventlet.wsgi.server(socket, application, custom_pool=self.pool, protocol=UnixDomainHttpProtocol, log=logging.WritableLogger(logger)) class UnixDomainMetadataProxy(object): OPTS = [ cfg.StrOpt('metadata_proxy_socket', default='$state_path/metadata_proxy', help=_('Location for Metadata Proxy UNIX domain socket')) ] def __init__(self, conf): self.conf = conf dirname = os.path.dirname(cfg.CONF.metadata_proxy_socket) if os.path.isdir(dirname): try: os.unlink(cfg.CONF.metadata_proxy_socket) except OSError: if os.path.exists(cfg.CONF.metadata_proxy_socket): raise else: os.makedirs(dirname, 0o755) def run(self): server = UnixDomainWSGIServer('neutron-metadata-agent') server.start(MetadataProxyHandler(self.conf), self.conf.metadata_proxy_socket) server.wait() def main(): eventlet.monkey_patch() cfg.CONF.register_opts(UnixDomainMetadataProxy.OPTS) cfg.CONF.register_opts(MetadataProxyHandler.OPTS) cfg.CONF(project='neutron') config.setup_logging(cfg.CONF) utils.log_opt_values(LOG) proxy = UnixDomainMetadataProxy(cfg.CONF) proxy.run()