# 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 from cinder.db import base from cinder import exception from cinder.i18n import _, _LE, _LI, _LW from cinder import quota from cinder.volume import api as volume_api 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): rv = self.db.transfer_get(context, transfer_id) return dict(rv.iteritems()) def delete(self, context, transfer_id): """Make the RPC call to delete a volume transfer.""" volume_api.check_policy(context, 'delete_transfer') transfer = self.db.transfer_get(context, transfer_id) volume_ref = self.db.volume_get(context, transfer.volume_id) if volume_ref['status'] != 'awaiting-transfer': LOG.error(_LE("Volume in unexpected state")) self.db.transfer_destroy(context, transfer_id) def get_all(self, context, filters=None): filters = filters or {} volume_api.check_policy(context, 'get_all_transfers') 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 hexidecimal 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.""" return hmac.new(str(salt), str(auth_key), hashlib.sha1).hexdigest() def create(self, context, volume_id, display_name): """Creates an entry in the transfers table.""" volume_api.check_policy(context, 'create_transfer') LOG.info(_LI("Generating transfer record for volume %s"), volume_id) volume_ref = self.db.volume_get(context, volume_id) if volume_ref['status'] != "available": raise exception.InvalidVolume(reason=_("status must be available")) # 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(_LE("Failed to create transfer record " "for %s"), volume_id) raise 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. volume_api.check_policy(context, 'accept_transfer') 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 = self.db.volume_get(context.elevated(), volume_id) try: reservations = QUOTAS.reserve(context, volumes=1, gigabytes=vol_ref['size']) except exception.OverQuota as e: overs = e.kwargs['overs'] usages = e.kwargs['usages'] quotas = e.kwargs['quotas'] def _consumed(name): return (usages[name]['reserved'] + usages[name]['in_use']) if 'gigabytes' in overs: msg = _LW("Quota exceeded for %(s_pid)s, tried to create " "%(s_size)sG volume (%(d_consumed)dG of " "%(d_quota)dG already consumed)") LOG.warning(msg, {'s_pid': context.project_id, 's_size': vol_ref['size'], 'd_consumed': _consumed('gigabytes'), 'd_quota': quotas['gigabytes']}) raise exception.VolumeSizeExceedsAvailableQuota( requested=vol_ref['size'], consumed=_consumed('gigabytes'), quota=quotas['gigabytes']) elif 'volumes' in overs: msg = _LW("Quota exceeded for %(s_pid)s, tried to create " "volume (%(d_consumed)d volumes " "already consumed)") LOG.warning(msg, {'s_pid': context.project_id, 'd_consumed': _consumed('volumes')}) raise exception.VolumeLimitExceeded(allowed=quotas['volumes']) try: donor_id = vol_ref['project_id'] donor_reservations = QUOTAS.reserve(context.elevated(), project_id=donor_id, volumes=-1, gigabytes=-vol_ref['size']) except Exception: donor_reservations = None LOG.exception(_LE("Failed to update quota donating volume" " transfer id %s"), transfer_id) 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(_LI("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) return {'id': transfer_id, 'display_name': transfer['display_name'], 'volume_id': vol_ref['id']}