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# vim: tabstop=4 shiftwidth=4 softtabstop=4

# Copyright 2010 United States Government as represented by the
# Administrator of the National Aeronautics and Space Administration.
# All Rights Reserved.
#
#    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.

"""Tests for metadata service."""

import base64
import copy
import hashlib
import hmac
import json
import re

try:
    import cPickle as pickle
except ImportError:
    import pickle

from oslo.config import cfg
import webob

from nova.api.metadata import base
from nova.api.metadata import handler
from nova.api.metadata import password
from nova import block_device
from nova.compute import flavors
from nova.conductor import api as conductor_api
from nova import db
from nova.db.sqlalchemy import api
from nova import exception
from nova.network import api as network_api
from nova import test
from nova.tests import fake_network
from nova import utils

CONF = cfg.CONF

USER_DATA_STRING = ("This is an encoded string")
ENCODE_USER_DATA_STRING = base64.b64encode(USER_DATA_STRING)

INSTANCES = (
    {'id': 1,
     'uuid': 'b65cee2f-8c69-4aeb-be2f-f79742548fc2',
     'name': 'fake',
     'project_id': 'test',
     'key_name': "mykey",
     'key_data': "ssh-rsa AAAAB3Nzai....N3NtHw== someuser@somehost",
     'host': 'test',
     'launch_index': 1,
     'instance_type': {'name': 'm1.tiny'},
     'reservation_id': 'r-xxxxxxxx',
     'user_data': ENCODE_USER_DATA_STRING,
     'image_ref': 7,
     'vcpus': 1,
     'fixed_ips': [],
     'root_device_name': '/dev/sda1',
     'info_cache': {'network_info': []},
     'hostname': 'test.novadomain',
     'display_name': 'my_displayname',
     'metadata': {}
    },
)


def get_default_sys_meta():
    return utils.dict_to_metadata(
        flavors.save_flavor_info(
            {}, flavors.get_default_flavor()))


def return_non_existing_address(*args, **kwarg):
    raise exception.NotFound()


def fake_InstanceMetadata(stubs, inst_data, address=None,
    sgroups=None, content=[], extra_md={}):

    if sgroups is None:
        sgroups = [{'name': 'default'}]

    def sg_get(*args, **kwargs):
        return sgroups

    stubs.Set(api, 'security_group_get_by_instance', sg_get)
    return base.InstanceMetadata(inst_data, address=address,
        content=content, extra_md=extra_md)


def fake_request(stubs, mdinst, relpath, address="127.0.0.1",
                 fake_get_metadata=None, headers=None,
                 fake_get_metadata_by_instance_id=None):

    def get_metadata_by_remote_address(address):
        return mdinst

    app = handler.MetadataRequestHandler()

    if fake_get_metadata is None:
        fake_get_metadata = get_metadata_by_remote_address

    if stubs:
        stubs.Set(app, 'get_metadata_by_remote_address', fake_get_metadata)

        if fake_get_metadata_by_instance_id:
            stubs.Set(app, 'get_metadata_by_instance_id',
                      fake_get_metadata_by_instance_id)

    request = webob.Request.blank(relpath)
    request.remote_addr = address

    if headers is not None:
        request.headers.update(headers)

    response = request.get_response(app)
    return response


class MetadataTestCase(test.TestCase):
    def setUp(self):
        super(MetadataTestCase, self).setUp()
        self.instance = INSTANCES[0]
        self.instance['system_metadata'] = get_default_sys_meta()
        self.flags(use_local=True, group='conductor')
        fake_network.stub_out_nw_api_get_instance_nw_info(self.stubs,
                                                          spectacular=True)

    def test_can_pickle_metadata(self):
        # Make sure that InstanceMetadata is possible to pickle. This is
        # required for memcache backend to work correctly.
        md = fake_InstanceMetadata(self.stubs, copy.copy(self.instance))
        pickle.dumps(md, protocol=0)

    def test_user_data(self):
        inst = copy.copy(self.instance)
        inst['user_data'] = base64.b64encode("happy")
        md = fake_InstanceMetadata(self.stubs, inst)
        self.assertEqual(
            md.get_ec2_metadata(version='2009-04-04')['user-data'], "happy")

    def test_no_user_data(self):
        inst = copy.copy(self.instance)
        del inst['user_data']
        md = fake_InstanceMetadata(self.stubs, inst)
        obj = object()
        self.assertEqual(
            md.get_ec2_metadata(version='2009-04-04').get('user-data', obj),
            obj)

    def test_security_groups(self):
        inst = copy.copy(self.instance)
        sgroups = [{'name': 'default'}, {'name': 'other'}]
        expected = ['default', 'other']

        md = fake_InstanceMetadata(self.stubs, inst, sgroups=sgroups)
        data = md.get_ec2_metadata(version='2009-04-04')
        self.assertEqual(data['meta-data']['security-groups'], expected)

    def test_local_hostname_fqdn(self):
        md = fake_InstanceMetadata(self.stubs, copy.copy(self.instance))
        data = md.get_ec2_metadata(version='2009-04-04')
        self.assertEqual(data['meta-data']['local-hostname'],
            "%s.%s" % (self.instance['hostname'], CONF.dhcp_domain))

    def test_format_instance_mapping(self):
        # Make sure that _format_instance_mappings works.
        ctxt = None
        instance_ref0 = {'id': 0,
                         'uuid': 'e5fe5518-0288-4fa3-b0c4-c79764101b85',
                         'root_device_name': None}
        instance_ref1 = {'id': 0,
                         'uuid': 'b65cee2f-8c69-4aeb-be2f-f79742548fc2',
                         'root_device_name': '/dev/sda1'}

        def fake_bdm_get(ctxt, uuid):
            return [{'volume_id': 87654321,
                     'snapshot_id': None,
                     'no_device': None,
                     'source_type': 'volume',
                     'destination_type': 'volume',
                     'delete_on_termination': True,
                     'device_name': '/dev/sdh'},
                    {'volume_id': None,
                     'snapshot_id': None,
                     'no_device': None,
                     'source_type': 'blank',
                     'destination_type': 'local',
                     'guest_format': 'swap',
                     'delete_on_termination': None,
                     'device_name': '/dev/sdc'},
                    {'volume_id': None,
                     'snapshot_id': None,
                     'no_device': None,
                     'source_type': 'blank',
                     'destination_type': 'local',
                     'guest_format': None,
                     'delete_on_termination': None,
                     'device_name': '/dev/sdb'}]

        self.stubs.Set(db, 'block_device_mapping_get_all_by_instance',
                       fake_bdm_get)

        expected = {'ami': 'sda1',
                    'root': '/dev/sda1',
                    'ephemeral0': '/dev/sdb',
                    'swap': '/dev/sdc',
                    'ebs0': '/dev/sdh'}

        capi = conductor_api.LocalAPI()

        self.assertEqual(base._format_instance_mapping(capi, ctxt,
                         instance_ref0), block_device._DEFAULT_MAPPINGS)
        self.assertEqual(base._format_instance_mapping(capi, ctxt,
                         instance_ref1), expected)

    def test_pubkey(self):
        md = fake_InstanceMetadata(self.stubs, copy.copy(self.instance))
        pubkey_ent = md.lookup("/2009-04-04/meta-data/public-keys")

        self.assertEqual(base.ec2_md_print(pubkey_ent),
            "0=%s" % self.instance['key_name'])
        self.assertEqual(base.ec2_md_print(pubkey_ent['0']['openssh-key']),
            self.instance['key_data'])

    def test_image_type_ramdisk(self):
        inst = copy.copy(self.instance)
        inst['ramdisk_id'] = 'ari-853667c0'
        md = fake_InstanceMetadata(self.stubs, inst)
        data = md.lookup("/latest/meta-data/ramdisk-id")

        self.assertTrue(data is not None)
        self.assertTrue(re.match('ari-[0-9a-f]{8}', data))

    def test_image_type_kernel(self):
        inst = copy.copy(self.instance)
        inst['kernel_id'] = 'aki-c2e26ff2'
        md = fake_InstanceMetadata(self.stubs, inst)
        data = md.lookup("/2009-04-04/meta-data/kernel-id")

        self.assertTrue(re.match('aki-[0-9a-f]{8}', data))

        self.assertEqual(
            md.lookup("/ec2/2009-04-04/meta-data/kernel-id"), data)

        del inst['kernel_id']
        md = fake_InstanceMetadata(self.stubs, inst)
        self.assertRaises(base.InvalidMetadataPath,
            md.lookup, "/2009-04-04/meta-data/kernel-id")

    def test_check_version(self):
        inst = copy.copy(self.instance)
        md = fake_InstanceMetadata(self.stubs, inst)

        self.assertTrue(md._check_version('1.0', '2009-04-04'))
        self.assertFalse(md._check_version('2009-04-04', '1.0'))

        self.assertFalse(md._check_version('2009-04-04', '2008-09-01'))
        self.assertTrue(md._check_version('2008-09-01', '2009-04-04'))

        self.assertTrue(md._check_version('2009-04-04', '2009-04-04'))


class OpenStackMetadataTestCase(test.TestCase):
    def setUp(self):
        super(OpenStackMetadataTestCase, self).setUp()
        self.instance = INSTANCES[0]
        self.instance['system_metadata'] = get_default_sys_meta()
        self.flags(use_local=True, group='conductor')
        fake_network.stub_out_nw_api_get_instance_nw_info(self.stubs,
                                                          spectacular=True)

    def test_top_level_listing(self):
        # request for /openstack/<version>/ should show metadata.json
        inst = copy.copy(self.instance)
        mdinst = fake_InstanceMetadata(self.stubs, inst)

        listing = mdinst.lookup("/openstack/")

        result = mdinst.lookup("/openstack")

        # trailing / should not affect anything
        self.assertEqual(result, mdinst.lookup("/openstack"))

        # the 'content' should not show up in directory listing
        self.assertTrue(base.CONTENT_DIR not in result)
        self.assertTrue('2012-08-10' in result)
        self.assertTrue('latest' in result)

    def test_version_content_listing(self):
        # request for /openstack/<version>/ should show metadata.json
        inst = copy.copy(self.instance)
        mdinst = fake_InstanceMetadata(self.stubs, inst)

        listing = mdinst.lookup("/openstack/2012-08-10")
        self.assertTrue("meta_data.json" in listing)

    def test_metadata_json(self):
        inst = copy.copy(self.instance)
        content = [
            ('/etc/my.conf', "content of my.conf"),
            ('/root/hello', "content of /root/hello"),
        ]

        mdinst = fake_InstanceMetadata(self.stubs, inst,
            content=content)
        mdjson = mdinst.lookup("/openstack/2012-08-10/meta_data.json")
        mdjson = mdinst.lookup("/openstack/latest/meta_data.json")

        mddict = json.loads(mdjson)

        self.assertEqual(mddict['uuid'], self.instance['uuid'])
        self.assertTrue('files' in mddict)

        self.assertTrue('public_keys' in mddict)
        self.assertEqual(mddict['public_keys'][self.instance['key_name']],
            self.instance['key_data'])

        self.assertTrue('launch_index' in mddict)
        self.assertEqual(mddict['launch_index'], self.instance['launch_index'])

        # verify that each of the things we put in content
        # resulted in an entry in 'files', that their content
        # there is as expected, and that /content lists them.
        for (path, content) in content:
            fent = [f for f in mddict['files'] if f['path'] == path]
            self.assertTrue((len(fent) == 1))
            fent = fent[0]
            found = mdinst.lookup("/openstack%s" % fent['content_path'])
            self.assertEqual(found, content)

    def test_extra_md(self):
        # make sure extra_md makes it through to metadata
        inst = copy.copy(self.instance)
        extra = {'foo': 'bar', 'mylist': [1, 2, 3],
                 'mydict': {"one": 1, "two": 2}}
        mdinst = fake_InstanceMetadata(self.stubs, inst, extra_md=extra)

        mdjson = mdinst.lookup("/openstack/2012-08-10/meta_data.json")
        mddict = json.loads(mdjson)

        for key, val in extra.iteritems():
            self.assertEqual(mddict[key], val)

    def test_password(self):
        # make sure extra_md makes it through to metadata
        inst = copy.copy(self.instance)
        mdinst = fake_InstanceMetadata(self.stubs, inst)

        result = mdinst.lookup("/openstack/latest/password")
        self.assertEqual(result, password.handle_password)

    def test_userdata(self):
        inst = copy.copy(self.instance)
        mdinst = fake_InstanceMetadata(self.stubs, inst)

        userdata_found = mdinst.lookup("/openstack/2012-08-10/user_data")
        self.assertEqual(USER_DATA_STRING, userdata_found)

        # since we had user-data in this instance, it should be in listing
        self.assertTrue('user_data' in mdinst.lookup("/openstack/2012-08-10"))

        del inst['user_data']
        mdinst = fake_InstanceMetadata(self.stubs, inst)

        # since this instance had no user-data it should not be there.
        self.assertFalse('user_data' in mdinst.lookup("/openstack/2012-08-10"))

        self.assertRaises(base.InvalidMetadataPath,
            mdinst.lookup, "/openstack/2012-08-10/user_data")

    def test_random_seed(self):
        inst = copy.copy(self.instance)
        mdinst = fake_InstanceMetadata(self.stubs, inst)

        # verify that 2013-04-04 has the 'random' field
        mdjson = mdinst.lookup("/openstack/2013-04-04/meta_data.json")
        mddict = json.loads(mdjson)

        self.assertTrue("random_seed" in mddict)
        self.assertEqual(len(base64.b64decode(mddict["random_seed"])), 512)

        # verify that older version do not have it
        mdjson = mdinst.lookup("/openstack/2012-08-10/meta_data.json")
        self.assertFalse("random_seed" in json.loads(mdjson))

    def test_no_dashes_in_metadata(self):
        # top level entries in meta_data should not contain '-' in their name
        inst = copy.copy(self.instance)
        mdinst = fake_InstanceMetadata(self.stubs, inst)
        mdjson = json.loads(mdinst.lookup("/openstack/latest/meta_data.json"))

        self.assertEqual([], [k for k in mdjson.keys() if k.find("-") != -1])


class MetadataHandlerTestCase(test.TestCase):
    """Test that metadata is returning proper values."""

    def setUp(self):
        super(MetadataHandlerTestCase, self).setUp()

        fake_network.stub_out_nw_api_get_instance_nw_info(self.stubs,
                                                          spectacular=True)
        self.instance = INSTANCES[0]
        self.instance['system_metadata'] = get_default_sys_meta()
        self.flags(use_local=True, group='conductor')
        self.mdinst = fake_InstanceMetadata(self.stubs, self.instance,
            address=None, sgroups=None)

    def test_callable(self):

        def verify(req, meta_data):
            self.assertTrue(isinstance(meta_data, CallableMD))
            return "foo"

        class CallableMD(object):
            def lookup(self, path_info):
                return verify

        response = fake_request(self.stubs, CallableMD(), "/bar")
        self.assertEqual(response.status_int, 200)
        self.assertEqual(response.body, "foo")

    def test_root(self):
        expected = "\n".join(base.VERSIONS) + "\nlatest"
        response = fake_request(self.stubs, self.mdinst, "/")
        self.assertEqual(response.body, expected)

        response = fake_request(self.stubs, self.mdinst, "/foo/../")
        self.assertEqual(response.body, expected)

    def test_version_root(self):
        response = fake_request(self.stubs, self.mdinst, "/2009-04-04")
        self.assertEqual(response.body, 'meta-data/\nuser-data')

        response = fake_request(self.stubs, self.mdinst, "/9999-99-99")
        self.assertEqual(response.status_int, 404)

    def test_user_data_non_existing_fixed_address(self):
        self.stubs.Set(network_api.API, 'get_fixed_ip_by_address',
                       return_non_existing_address)
        response = fake_request(None, self.mdinst, "/2009-04-04/user-data",
                                "127.1.1.1")
        self.assertEqual(response.status_int, 404)

    def test_fixed_address_none(self):
        response = fake_request(None, self.mdinst,
                                relpath="/2009-04-04/user-data", address=None)
        self.assertEqual(response.status_int, 500)

    def test_invalid_path_is_404(self):
        response = fake_request(self.stubs, self.mdinst,
                                relpath="/2009-04-04/user-data-invalid")
        self.assertEqual(response.status_int, 404)

    def test_user_data_with_use_forwarded_header(self):
        expected_addr = "192.192.192.2"

        def fake_get_metadata(address):
            if address == expected_addr:
                return self.mdinst
            else:
                raise Exception("Expected addr of %s, got %s" %
                                (expected_addr, address))

        self.flags(use_forwarded_for=True)
        response = fake_request(self.stubs, self.mdinst,
                                relpath="/2009-04-04/user-data",
                                address="168.168.168.1",
                                fake_get_metadata=fake_get_metadata,
                                headers={'X-Forwarded-For': expected_addr})

        self.assertEqual(response.status_int, 200)
        self.assertEqual(response.body,
                         base64.b64decode(self.instance['user_data']))

        response = fake_request(self.stubs, self.mdinst,
                                relpath="/2009-04-04/user-data",
                                address="168.168.168.1",
                                fake_get_metadata=fake_get_metadata,
                                headers=None)
        self.assertEqual(response.status_int, 500)

    def test_user_data_with_quantum_instance_id(self):
        expected_instance_id = 'a-b-c-d'

        def fake_get_metadata(instance_id, remote_address):
            if remote_address is None:
                raise Exception('Expected X-Forwared-For header')
            elif instance_id == expected_instance_id:
                return self.mdinst
            else:
                # raise the exception to aid with 500 response code test
                raise Exception("Expected instance_id of %s, got %s" %
                                (expected_instance_id, instance_id))

        signed = hmac.new(
            CONF.quantum_metadata_proxy_shared_secret,
            expected_instance_id,
            hashlib.sha256).hexdigest()

        # try a request with service disabled
        response = fake_request(
            self.stubs, self.mdinst,
            relpath="/2009-04-04/user-data",
            address="192.192.192.2",
            headers={'X-Instance-ID': 'a-b-c-d',
                     'X-Instance-ID-Signature': signed})
        self.assertEqual(response.status_int, 200)

        # now enable the service
        self.flags(service_quantum_metadata_proxy=True)
        response = fake_request(
            self.stubs, self.mdinst,
            relpath="/2009-04-04/user-data",
            address="192.192.192.2",
            fake_get_metadata_by_instance_id=fake_get_metadata,
            headers={'X-Forwarded-For': '192.192.192.2',
                     'X-Instance-ID': 'a-b-c-d',
                     'X-Instance-ID-Signature': signed})

        self.assertEqual(response.status_int, 200)
        self.assertEqual(response.body,
                         base64.b64decode(self.instance['user_data']))

        # mismatched signature
        response = fake_request(
            self.stubs, self.mdinst,
            relpath="/2009-04-04/user-data",
            address="192.192.192.2",
            fake_get_metadata_by_instance_id=fake_get_metadata,
            headers={'X-Forwarded-For': '192.192.192.2',
                     'X-Instance-ID': 'a-b-c-d',
                     'X-Instance-ID-Signature': ''})

        self.assertEqual(response.status_int, 403)

        # without X-Forwarded-For
        response = fake_request(
            self.stubs, self.mdinst,
            relpath="/2009-04-04/user-data",
            address="192.192.192.2",
            fake_get_metadata_by_instance_id=fake_get_metadata,
            headers={'X-Instance-ID': 'a-b-c-d',
                     'X-Instance-ID-Signature': signed})

        self.assertEqual(response.status_int, 500)

        # unexpected Instance-ID
        signed = hmac.new(
            CONF.quantum_metadata_proxy_shared_secret,
           'z-z-z-z',
           hashlib.sha256).hexdigest()

        response = fake_request(
            self.stubs, self.mdinst,
            relpath="/2009-04-04/user-data",
            address="192.192.192.2",
            fake_get_metadata_by_instance_id=fake_get_metadata,
            headers={'X-Forwarded-For': '192.192.192.2',
                     'X-Instance-ID': 'z-z-z-z',
                     'X-Instance-ID-Signature': signed})
        self.assertEqual(response.status_int, 500)


class MetadataPasswordTestCase(test.TestCase):
    def setUp(self):
        super(MetadataPasswordTestCase, self).setUp()
        fake_network.stub_out_nw_api_get_instance_nw_info(self.stubs,
                                                          spectacular=True)
        self.instance = copy.copy(INSTANCES[0])
        self.instance['system_metadata'] = get_default_sys_meta()
        self.flags(use_local=True, group='conductor')
        self.mdinst = fake_InstanceMetadata(self.stubs, self.instance,
            address=None, sgroups=None)
        self.flags(use_local=True, group='conductor')

    def test_get_password(self):
        request = webob.Request.blank('')
        self.mdinst.password = 'foo'
        result = password.handle_password(request, self.mdinst)
        self.assertEqual(result, 'foo')

    def test_bad_method(self):
        request = webob.Request.blank('')
        request.method = 'PUT'
        self.assertRaises(webob.exc.HTTPBadRequest,
                          password.handle_password, request, self.mdinst)

    def _try_set_password(self, val='bar'):
        request = webob.Request.blank('')
        request.method = 'POST'
        request.body = val
        self.stubs.Set(db, 'instance_get_by_uuid',
                       lambda *a, **kw: {'system_metadata': []})

        def fake_instance_update(context, uuid, updates):
            self.assertIn('system_metadata', updates)
            self.assertIn('password_0', updates['system_metadata'])
            return self.instance, self.instance

        self.stubs.Set(db, 'instance_update_and_get_original',
                       fake_instance_update)
        password.handle_password(request, self.mdinst)

    def test_set_password(self):
        self.mdinst.password = ''
        self._try_set_password()

    def test_conflict(self):
        self.mdinst.password = 'foo'
        self.assertRaises(webob.exc.HTTPConflict,
                          self._try_set_password)

    def test_too_large(self):
        self.mdinst.password = ''
        self.assertRaises(webob.exc.HTTPBadRequest,
                          self._try_set_password,
                          'a' * (password.MAX_SIZE + 1))