# Copyright (C) 2013 Hewlett-Packard Development Company, L.P. # 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. """ Handles all requests relating to transferring ownership of volumes. """ import hashlib import hmac import os from oslo_config import cfg from oslo_log import log as logging from oslo_utils import excutils import six from cinder.db import base from cinder import exception from cinder.i18n import _ from cinder import objects from cinder.policies import volume_transfer as policy from cinder import quota from cinder import quota_utils from cinder.volume import api as volume_api from cinder.volume import utils as volume_utils volume_transfer_opts = [ cfg.IntOpt('volume_transfer_salt_length', default=8, help='The number of characters in the salt.'), cfg.IntOpt('volume_transfer_key_length', default=16, help='The number of characters in the ' 'autogenerated auth key.'), ] CONF = cfg.CONF CONF.register_opts(volume_transfer_opts) LOG = logging.getLogger(__name__) QUOTAS = quota.QUOTAS class API(base.Base): """API for interacting volume transfers.""" def __init__(self, db_driver=None): self.volume_api = volume_api.API() super(API, self).__init__(db_driver) def get(self, context, transfer_id): context.authorize(policy.GET_POLICY) rv = self.db.transfer_get(context, transfer_id) return dict(rv) def delete(self, context, transfer_id): """Make the RPC call to delete a volume transfer.""" transfer = self.db.transfer_get(context, transfer_id) volume_ref = self.db.volume_get(context, transfer.volume_id) context.authorize(policy.DELETE_POLICY, target_obj=volume_ref) volume_utils.notify_about_volume_usage(context, volume_ref, "transfer.delete.start") if volume_ref['status'] != 'awaiting-transfer': LOG.error("Volume in unexpected state") self.db.transfer_destroy(context, transfer_id) volume_utils.notify_about_volume_usage(context, volume_ref, "transfer.delete.end") def get_all(self, context, filters=None): filters = filters or {} context.authorize(policy.GET_ALL_POLICY) if context.is_admin and 'all_tenants' in filters: transfers = self.db.transfer_get_all(context) else: transfers = self.db.transfer_get_all_by_project(context, context.project_id) return transfers def _get_random_string(self, length): """Get a random hex string of the specified length.""" rndstr = "" # Note that the string returned by this function must contain only # characters that the recipient can enter on their keyboard. The # function ssh224().hexdigit() achieves this by generating a hash # which will only contain hexadecimal digits. while len(rndstr) < length: rndstr += hashlib.sha224(os.urandom(255)).hexdigest() return rndstr[0:length] def _get_crypt_hash(self, salt, auth_key): """Generate a random hash based on the salt and the auth key.""" if not isinstance(salt, (six.binary_type, six.text_type)): salt = str(salt) if isinstance(salt, six.text_type): salt = salt.encode('utf-8') if not isinstance(auth_key, (six.binary_type, six.text_type)): auth_key = str(auth_key) if isinstance(auth_key, six.text_type): auth_key = auth_key.encode('utf-8') return hmac.new(salt, auth_key, hashlib.sha1).hexdigest() def create(self, context, volume_id, display_name): """Creates an entry in the transfers table.""" LOG.info("Generating transfer record for volume %s", volume_id) volume_ref = self.db.volume_get(context, volume_id) context.authorize(policy.CREATE_POLICY, target_obj=volume_ref) if volume_ref['status'] != "available": raise exception.InvalidVolume(reason=_("status must be available")) if volume_ref['encryption_key_id'] is not None: raise exception.InvalidVolume( reason=_("transferring encrypted volume is not supported")) volume_utils.notify_about_volume_usage(context, volume_ref, "transfer.create.start") # The salt is just a short random string. salt = self._get_random_string(CONF.volume_transfer_salt_length) auth_key = self._get_random_string(CONF.volume_transfer_key_length) crypt_hash = self._get_crypt_hash(salt, auth_key) # TODO(ollie): Transfer expiry needs to be implemented. transfer_rec = {'volume_id': volume_id, 'display_name': display_name, 'salt': salt, 'crypt_hash': crypt_hash, 'expires_at': None} try: transfer = self.db.transfer_create(context, transfer_rec) except Exception: LOG.error("Failed to create transfer record for %s", volume_id) raise volume_utils.notify_about_volume_usage(context, volume_ref, "transfer.create.end") return {'id': transfer['id'], 'volume_id': transfer['volume_id'], 'display_name': transfer['display_name'], 'auth_key': auth_key, 'created_at': transfer['created_at']} def accept(self, context, transfer_id, auth_key): """Accept a volume that has been offered for transfer.""" # We must use an elevated context to see the volume that is still # owned by the donor. context.authorize(policy.ACCEPT_POLICY) transfer = self.db.transfer_get(context.elevated(), transfer_id) crypt_hash = self._get_crypt_hash(transfer['salt'], auth_key) if crypt_hash != transfer['crypt_hash']: msg = (_("Attempt to transfer %s with invalid auth key.") % transfer_id) LOG.error(msg) raise exception.InvalidAuthKey(reason=msg) volume_id = transfer['volume_id'] vol_ref = objects.Volume.get_by_id(context.elevated(), volume_id) if vol_ref['consistencygroup_id']: msg = _("Volume %s must not be part of a consistency " "group.") % vol_ref['id'] LOG.error(msg) raise exception.InvalidVolume(reason=msg) try: values = {'per_volume_gigabytes': vol_ref.size} QUOTAS.limit_check(context, project_id=context.project_id, **values) except exception.OverQuota as e: quotas = e.kwargs['quotas'] raise exception.VolumeSizeExceedsLimit( size=vol_ref.size, limit=quotas['per_volume_gigabytes']) try: reserve_opts = {'volumes': 1, 'gigabytes': vol_ref.size} QUOTAS.add_volume_type_opts(context, reserve_opts, vol_ref.volume_type_id) reservations = QUOTAS.reserve(context, **reserve_opts) except exception.OverQuota as e: quota_utils.process_reserve_over_quota(context, e, resource='volumes', size=vol_ref.size) try: donor_id = vol_ref['project_id'] reserve_opts = {'volumes': -1, 'gigabytes': -vol_ref.size} QUOTAS.add_volume_type_opts(context, reserve_opts, vol_ref.volume_type_id) donor_reservations = QUOTAS.reserve(context.elevated(), project_id=donor_id, **reserve_opts) except Exception: donor_reservations = None LOG.exception("Failed to update quota donating volume" " transfer id %s", transfer_id) volume_utils.notify_about_volume_usage(context, vol_ref, "transfer.accept.start") try: # Transfer ownership of the volume now, must use an elevated # context. self.volume_api.accept_transfer(context, vol_ref, context.user_id, context.project_id) self.db.transfer_accept(context.elevated(), transfer_id, context.user_id, context.project_id) QUOTAS.commit(context, reservations) if donor_reservations: QUOTAS.commit(context, donor_reservations, project_id=donor_id) LOG.info("Volume %s has been transferred.", volume_id) except Exception: with excutils.save_and_reraise_exception(): QUOTAS.rollback(context, reservations) if donor_reservations: QUOTAS.rollback(context, donor_reservations, project_id=donor_id) vol_ref = self.db.volume_get(context, volume_id) volume_utils.notify_about_volume_usage(context, vol_ref, "transfer.accept.end") return {'id': transfer_id, 'display_name': transfer['display_name'], 'volume_id': vol_ref['id']}