burp-ui/burpui/api/async.py
2017-02-06 21:23:31 +01:00

1088 lines
32 KiB
Python

# -*- coding: utf8 -*-
"""
.. module:: burpui.api.async
:platform: Unix
:synopsis: Burp-UI async api module.
.. moduleauthor:: Ziirish <hi+burpui@ziirish.me>
"""
import os
import select
import struct
from . import api, cache_key
from .misc import History
from .custom import Resource
from .client import ClientTreeAll, node_fields
from .clients import RunningBackup, ClientsReport
from ..exceptions import BUIserverException
from ..server import BUIServer # noqa
from ..sessions import session_manager
from ..ext.async import celery
from ..ext.cache import cache
from ..config import config
from ..decorators import browser_cache
from six import iteritems
from zlib import adler32
from flask import url_for, Response, current_app, after_this_request, \
send_file, redirect
from time import gmtime, strftime, time, sleep
from datetime import timedelta, datetime
from werkzeug.datastructures import Headers
from celery.schedules import crontab
from celery.utils.log import get_task_logger
if config.get('WITH_SQL'):
from ..ext.sql import db
else:
db = None
bui = current_app # type: BUIServer
ns = api.namespace('async', 'Asynchronous methods')
logger = get_task_logger(__name__)
ME = __name__
LOCK_EXPIRE = 60 * 30 # Lock expires in 30 minutes
BEAT_SCHEDULE = {
'ping-backend-hourly': {
'task': '{}.ping_backend'.format(ME),
'schedule': crontab(minute='15'), # run every hour
},
'backup-running-minutely': {
'task': '{}.backup_running'.format(ME),
'schedule': crontab(), # run every minute
},
'get-all-backups-every-twenty-minutes': {
'task': '{}.get_all_backups'.format(ME),
'schedule': crontab(minute='*/20'), # every 20 minutes
},
'get-all-clients-reports-every-twenty-minutes': {
'task': '{}.get_all_clients_reports'.format(ME),
'schedule': crontab(minute='*/20'), # every 20 minutes
},
'cleanup-expired-sessions-daily': {
'task': '{}.cleanup_expired_sessions'.format(ME),
'schedule': crontab(hour='1'), # every day at 1
},
}
if db:
from ..models import Task
BEAT_SCHEDULE.update({
'cleanup-restore-hourly': {
'task': '{}.cleanup_restore'.format(ME),
'schedule': crontab(minute='12'), # run every hour
},
})
if 'CELERYBEAT_SCHEDULE' in celery.conf and \
isinstance(celery.conf['CELERYBEAT_SCHEDULE'], dict):
celery.conf['CELERYBEAT_SCHEDULE'].update(BEAT_SCHEDULE)
else:
celery.conf['CELERYBEAT_SCHEDULE'] = BEAT_SCHEDULE
def acquire_lock(name, value='nyan', timeout=LOCK_EXPIRE):
"""Utility function to acquire a lock before processing the request"""
lock = cache.cache.get(name)
if lock:
acquire_lock.lock = lock
return False
return cache.cache.add(name, value, timeout)
acquire_lock.lock = None
def release_lock(name):
"""Utility function to release a lock"""
return cache.cache.delete(name)
def wait_for(lock_name, value, wait=10, timeout=LOCK_EXPIRE):
"""Utility function to wait until the given lock has been released"""
old_lock = None
if not acquire_lock(lock_name, value, timeout):
logger.warn(
'A task is already running. Wait for it: {}/{}'.format(
lock_name,
acquire_lock.lock
)
)
old_lock = acquire_lock.lock
# The lock should be released after LOCK_EXPLIRE max
while not acquire_lock(lock_name, value, timeout):
sleep(wait)
# TODO: maybe we should check the status of task referenced by"old_lock"
# to make sure the lock did not expire and the task is actually over
logger.debug('lock released by: {}'.format(old_lock))
return old_lock
@celery.task
def ping_backend():
if bui.standalone:
bui.client.status()
else:
def __status(server):
(serv, back) = server
try:
return bui.client.status(agent=serv)
except BUIserverException:
return False
map(
__status,
iteritems(bui.client.servers)
)
@celery.task(bind=True)
def backup_running(self):
# run once at the time, if one task was already running, we just discard
# the new attempt
if not acquire_lock(self.name):
return None
try:
cache.cache.set(
'backup_running_result',
bui.client.is_one_backup_running(),
120
)
finally:
release_lock(self.name)
@celery.task(bind=True)
def get_all_backups(self):
# run once at the time, if one task was already running, we just discard
# the new attempt
if not acquire_lock(self.name):
return None
try:
backups = {}
if bui.standalone:
for cli in bui.client.get_all_clients():
backups[cli['name']] = bui.client.get_client(cli['name'])
else:
for serv in bui.client.servers:
backups[serv] = {}
for cli in bui.client.get_all_clients(agent=serv):
backups[serv][cli['name']] = bui.client.get_client(cli['name'], agent=serv)
cache.cache.set('all_backups', backups, 3600)
finally:
release_lock(self.name)
@celery.task(bind=True)
def get_all_clients_reports(self):
# run once at the time, if one task was already running, we just discard
# the new attempt
if not acquire_lock(self.name):
return None
try:
reports = {}
if bui.standalone:
reports = bui.client.get_clients_report(bui.client.get_all_clients())
else:
for serv in bui.client.servers:
reports[serv] = bui.client.get_clients_report(bui.client.get_all_clients(agent=serv), serv)
cache.cache.set('all_clients_reports', reports, 3600)
finally:
release_lock(self.name)
@celery.task
def cleanup_expired_sessions():
def expires(sess):
ret = session_manager.invalidate_session_by_id(sess.uuid)
if ret:
session_manager.delete_session_by_id(sess.uuid)
return ret
map(expires, session_manager.get_expired_sessions())
@celery.task
def cleanup_restore():
tasks = db.session.query(Task).filter(Task.task == 'perform_restore').filter(datetime.utcnow() > Task.expire).all()
# tasks = Task.query.filter_by(task='perform_restore').all()
for rec in tasks:
# if rec.expire and datetime.utcnow() > rec.expire:
logger.info('Task expired: {}'.format(rec))
task = perform_restore.AsyncResult(rec.uuid)
try:
if task.state != 'SUCCESS':
logger.warn(
'Task is not done yet or did not end '
'successfully: {}'.format(task.state)
)
task.revoke(terminate=True)
continue
if not task.result:
logger.warn('The task did not return anything')
continue
server = task.result.get('server')
path = task.result.get('path')
if path:
if server:
if not bui.client.del_file(path, agent=server):
logger.warn("'{}' already removed".format(path))
else:
if os.path.isfile(path):
os.unlink(path)
finally:
db.session.delete(rec)
db.session.commit()
task.revoke()
@celery.task(bind=True)
def perform_restore(self, client, backup,
files, strip, fmt, passwd, server=None, user=None,
expire=timedelta(minutes=60)):
ret = None
lock_name = '{}-{}'.format(self.name, server)
# TODO: maybe do something with old_lock someday
wait_for(lock_name, self.request.id)
try:
if server:
filename = 'restoration_%d_%s_on_%s_at_%s.%s' % (
backup,
client,
server,
strftime("%Y-%m-%d_%H_%M_%S", gmtime()),
fmt)
else:
filename = 'restoration_%d_%s_at_%s.%s' % (
backup,
client,
strftime("%Y-%m-%d_%H_%M_%S", gmtime()),
fmt)
self.update_state(state='STARTED', meta={'step': 'doing'})
archive, err = bui.client.restore_files(
client,
backup,
files,
strip,
fmt,
passwd,
server
)
if not archive:
if not err:
err = 'Something went wrong while restoring'
self.update_state(state='FAILURE', meta={'error': err})
logger.error('FAILURE: {}'.format(err))
else:
ret = {
'filename': filename,
'path': archive,
'user': user,
'server': server
}
logger.debug(ret)
finally:
release_lock(lock_name)
if db:
curr = Task.query.filter_by(uuid=self.request.id).first()
if curr:
curr.expire = datetime.utcnow() + expire
db.session.commit()
if err:
# make the task crash
raise Exception(err)
return ret
@celery.task(bind=True)
def load_all_tree(self, client, backup, server=None, user=None):
key = 'load_all_tree-{}-{}-{}'.format(client, backup, server)
ret = cache.cache.get(key)
if ret:
return {
'client': client,
'backup': backup,
'server': server,
'user': user,
'tree': ret
}
lock_name = '{}-{}'.format(self.name, server)
# TODO: maybe do something with old_lock someday
wait_for(lock_name, self.request.id)
try:
ret = ClientTreeAll._get_tree_all(client, backup, server)
except BUIserverException as exp:
raise Exception(str(exp))
finally:
release_lock(lock_name)
cache.cache.set(key, ret, 3600)
return {
'client': client,
'backup': backup,
'server': server,
'user': user,
'tree': ret
}
def force_scheduling_now():
"""Force scheduling some tasks now"""
get_all_backups.delay()
backup_running.delay()
get_all_clients_reports.delay()
@ns.route('/status/<task_id>', endpoint='async_restore_status')
@ns.doc(
params={
'task_id': 'The task ID to process',
}
)
class AsyncRestoreStatus(Resource):
"""The :class:`burpui.api.async.AsyncRestoreStatus` resource allows you to
follow a restore task.
This resource is part of the :mod:`burpui.api.async` module.
"""
@ns.doc(
responses={
200: 'Success',
500: 'Task failed',
},
)
def get(self, task_id):
"""Returns the state of the given task"""
task = perform_restore.AsyncResult(task_id)
if task.state == 'FAILURE':
if db:
rec = Task.query.filter_by(uuid=task_id).first()
if rec:
db.session.delete(rec)
db.session.commit()
task.revoke()
err = str(task.result)
self.abort(502, err)
if task.state == 'SUCCESS':
if not task.result:
self.abort(500, 'The task did not return anything')
server = task.result.get('server')
return {
'state': task.state,
'location': url_for(
'.async_get_file',
task_id=task_id,
server=server
)
}
return {'state': task.state}
@ns.route('/get/<task_id>',
'/<server>/get/<task_id>',
endpoint='async_get_file')
@ns.doc(
params={
'server': 'Which server to collect data from when in multi-agent mode',
'task_id': 'The task ID to process',
}
)
class AsyncGetFile(Resource):
"""The :class:`burpui.api.async.AsyncGetFile` resource allows you to
retrieve the archive generated by the given task.
This resource is part of the :mod:`burpui.api.async` module.
"""
@ns.doc(
responses={
200: 'Success',
400: 'Incomplete task',
403: 'Insufficient permissions',
500: 'Task failed',
},
)
def get(self, task_id, server=None):
"""Returns the generated archive"""
task = perform_restore.AsyncResult(task_id)
if task.state != 'SUCCESS':
if task.state == 'FAILURE':
self.abort(
500,
'Unsuccessful task: {}'.format(task.result.get('error'))
)
self.abort(400, 'Task not processed yet: {}'.format(task.state))
path = task.result.get('path')
user = task.result.get('user')
dst_server = task.result.get('server')
filename = task.result.get('filename')
if self.username != user or (dst_server and dst_server != server):
self.abort(403, 'Unauthorized access')
if db:
rec = Task.query.filter_by(uuid=task_id).first()
if rec:
db.session.delete(rec)
db.session.commit()
task.revoke()
if dst_server:
return self.stream_file(path, filename, dst_server)
try:
# Trick to delete the file while sending it to the client.
# First, we open the file in reading mode so that a file handler
# is open on the file. Then we delete it as soon as the request
# ended. Because the fh is open, the file will be actually removed
# when the transfer is done and the send_file method has closed
# the fh. Only tested on Linux systems.
fh = open(path, 'r')
@after_this_request
def remove_file(response):
"""Callback function to run after the client has handled
the request to remove temporary files.
"""
os.remove(path)
return response
resp = send_file(fh,
as_attachment=True,
attachment_filename=filename,
mimetype='application/zip')
resp.set_cookie('fileDownload', 'true')
except Exception as e:
bui.client.logger.error(str(e))
self.abort(500, str(e))
return resp
def stream_file(self, path, filename, server):
socket = bui.client.get_file(path, server)
if not socket:
self.abort(500)
lengthbuf = socket.recv(8)
length, = struct.unpack('!Q', lengthbuf)
def stream(sock, l):
"""The restoration took place on another server so we need
to stream the file that is not present on the current
machine.
"""
bsize = 1024
received = 0
if l < bsize:
bsize = l
while received < l:
buf = b''
r, _, _ = select.select([sock], [], [], 5)
if not r:
self.abort(500, 'Socket timed-out')
buf += sock.recv(bsize)
if not buf:
continue
received += len(buf)
self.logger.debug('{}/{}'.format(received, l))
yield buf
sock.sendall(struct.pack('!Q', 2))
sock.sendall(b'RE')
sock.close()
headers = Headers()
headers.add('Content-Disposition',
'attachement',
filename=filename)
headers['Content-Length'] = length
resp = Response(stream(socket, length),
mimetype='application/zip',
headers=headers,
direct_passthrough=True)
resp.set_cookie('fileDownload', 'true')
resp.set_etag('flask-%s-%s-%s' % (
time(),
length,
adler32(filename.encode('utf-8')) & 0xffffffff))
return resp
@ns.route('/archive/<name>/<int:backup>',
'/<server>/archive/<name>/<int:backup>',
endpoint='async_restore')
@ns.doc(
params={
'server': 'Which server to collect data from when in multi-agent mode',
'name': 'Client name',
'backup': 'Backup number',
},
)
class AsyncRestore(Resource):
"""The :class:`burpui.api.async.AsyncRestore` resource allows you to
perform a file restoration.
This resource is part of the :mod:`burpui.api.async` module.
The following parameters are supported:
- ``list``: list of files/directories to restore
- ``strip``: number of elements to strip in the path
- ``format``: returning archive format
- ``pass``: password to use for encrypted backups
"""
parser = ns.parser()
parser.add_argument(
'pass',
help='Password to use for encrypted backups',
nullable=True
)
parser.add_argument(
'format',
required=False,
help='Returning archive format',
choices=('zip', 'tar.gz', 'tar.bz2'),
default='zip',
nullable=True
)
parser.add_argument(
'strip',
type=int,
help='Number of elements to strip in the path',
default=0,
nullable=True
)
parser.add_argument(
'list',
required=True,
help='List of files/directories to restore',
nullable=False
)
@ns.expect(parser, validate=True)
@ns.doc(
responses={
202: 'Accepted',
400: 'Missing parameter',
403: 'Insufficient permissions',
},
)
def post(self, server=None, name=None, backup=None):
"""Performs an online restoration
**POST** method provided by the webservice.
This method returns a :mod:`flask.Response` object.
:param server: Which server to collect data from when in multi-agent
mode
:type server: str
:param name: The client we are working on
:type name: str
:param backup: The backup we are working on
:type backup: int
"""
args = self.parser.parse_args()
files = args['list']
strip = args['strip']
fmt = args['format'] or 'zip'
passwd = args['pass']
if not files or not name or not backup:
self.abort(400, 'missing arguments')
# Manage ACL
if (bui.acl and
(not bui.acl.is_client_allowed(self.username,
name,
server) and not
self.is_admin)):
self.abort(
403,
'You are not allowed to perform a restoration for this client'
)
task = perform_restore.apply_async(
args=[
name,
backup,
files,
strip,
fmt,
passwd,
server,
self.username
]
)
if db:
db_task = Task(
task.id,
'perform_restore',
self.username,
timedelta(minutes=60)
)
db.session.add(db_task)
db.session.commit()
return {'id': task.id, 'name': 'perform_restore'}, 202
@ns.route('/backup-running',
'/<server>/backup-running',
endpoint='async_running_backup')
@ns.doc(
params={
'server': 'Which server to collect data from when in multi-agent mode',
}
)
class AsyncRunningBackup(RunningBackup):
"""The :class:`burpui.api.async.AsyncRunningBackup` resource allows you to
access the status of the server in order to know if there is a running
backup currently.
This resource is backed by a periodic task. If the periodic task fail or is
not running, we redirect to the "synchronous" API call.
This resource is part of the :mod:`burpui.api.async` module.
"""
@ns.marshal_with(
RunningBackup.running_fields,
code=200,
description='Success',
strict=False
)
def get(self, server=None):
"""Tells if a backup is running right now
**GET** method provided by the webservice.
The *JSON* returned is:
::
{
"running": false
}
The output is filtered by the :mod:`burpui.misc.acl` module so that you
only see stats about the clients you are authorized to.
:param server: Which server to collect data from when in multi-agent
mode
:type server: str
:returns: The *JSON* described above.
"""
res = cache.cache.get('backup_running_result')
if res is None:
# redirect to synchronous API call
# FIXME: Since we subclass the original code, we don't need the
# redirect anymore if the redirection is problematic
return redirect(url_for('api.running_backup', server=server))
return {'running': self._is_one_backup_running(res, server)}
@ns.route('/history',
'/history/<client>',
'/<server>/history',
'/<server>/history/<client>',
endpoint='async_history')
@ns.doc(
params={
'server': 'Which server to collect data from when in multi-agent mode',
'client': 'Client name',
},
)
class AsyncHistory(History):
"""The :class:`burpui.api.misc.History` resource allows you to retrieve
an history of the backups
This resource is backed by a periodic task. If the periodic task fail or is
not running, we redirect to the "synchronous" API call.
An optional ``GET`` parameter called ``serverName`` is supported when
running in multi-agent mode and ``clientName`` is also allowed to filter
by client.
::
$('#calendar').fullCalendar({
eventSources: [
// your event source
{
events: [ // put the array in the `events` property
{
title : 'event1',
start : '2010-01-01'
},
{
title : 'event2',
start : '2010-01-05',
end : '2010-01-07'
},
{
title : 'event3',
start : '2010-01-09T12:30:00',
}
],
color: 'black', // an option!
textColor: 'yellow' // an option!
}
// any other event sources...
]
});
"""
@cache.cached(timeout=1800, key_prefix=cache_key)
@browser_cache(1800)
@ns.marshal_with(
History.history_fields,
code=200,
description='Success',
strict=False,
as_list=True
)
@ns.expect(History.parser)
@ns.doc(
responses={
200: 'Success',
403: 'Insufficient permissions',
},
)
def get(self, client=None, server=None):
"""Returns a list of calendars describing the backups that have been
completed so far
**GET** method provided by the webservice.
The *JSON* returned is:
::
[
{
"color": "#7C6F44",
"events": [
{
"backup": "0000001",
"end": "2015-01-25 13:32:04+01:00",
"name": "toto-test",
"start": "2015-01-25 13:32:00+01:00",
"title": "Client: toto-test, Backup n°0000001",
"url": "/client/toto-test"
}
],
"name": "toto-test",
"textColor": "white"
}
]
The output is filtered by the :mod:`burpui.misc.acl` module so that you
only see stats about the clients you are authorized to.
:param server: Which server to collect data from when in multi-agent mode
:type server: str
:param client: Which client to collect data from
:type client: str
:returns: The *JSON* described above
"""
self._check_acl(client, server)
res = cache.cache.get('all_backups')
args = self.parser.parse_args()
if res is None:
# redirect to synchronous API call
# FIXME: Since we subclass the original code, we don't need the
# redirect anymore if the redirection is problematic
return redirect(
url_for(
'api.history',
client=client,
server=server,
start=args['start'],
end=args['end']
)
)
return self._get_backup_history(client, server, res)
@ns.route('/report',
'/<server>/report',
endpoint='async_clients_report')
@ns.doc(
params={
'server': 'Which server to collect data from when in multi-agent mode',
},
)
class AsyncClientsReport(ClientsReport):
"""The :class:`burpui.api.async.AsyncClientsReport` resource allows you to
access general reports about your clients.
This resource is part of the :mod:`burpui.api.clients` module.
An optional ``GET`` parameter called ``serverName`` is supported when
running in multi-agent mode.
"""
@api.cache.cached(timeout=1800, key_prefix=cache_key)
@browser_cache(1800)
@ns.marshal_with(
ClientsReport.report_fields,
code=200,
description='Success',
strict=False
)
@ns.expect(ClientsReport.parser)
@ns.doc(
responses={
403: 'Insufficient permissions',
500: 'Internal failure',
},
)
def get(self, server=None):
"""Returns a global report about all the clients of a given server
**GET** method provided by the webservice.
The *JSON* returned is:
::
{
"backups": [
{
"name": "client1",
"number": 15
},
{
"name": "client2",
"number": 1
}
],
"clients": [
{
"name": "client1",
"stats": {
"total": 296377,
"totsize": 57055793698,
"windows": "unknown"
}
},
{
"name": "client2",
"stats": {
"total": 3117,
"totsize": 5345361,
"windows": "true"
}
}
]
}
The output is filtered by the :mod:`burpui.misc.acl` module so that you
only see stats about the clients you are authorized to.
:param server: Which server to collect data from when in multi-agent
mode
:type server: str
:returns: The *JSON* described above
"""
server = server or self.parser.parse_args()['serverName']
self._check_acl(server)
res = cache.cache.get('all_clients_reports')
if res is None:
# redirect to synchronous API call
# FIXME: Since we subclass the original code, we don't need the
# redirect anymore if the redirection is problematic
return redirect(url_for('api.clients_report', server=server))
return self._get_clients_reports(res, server)
@ns.route('/browseall/<name>/<int:backup>',
'/<server>/browsall/<name>/<int:backup>',
endpoint='async_client_tree_all')
@ns.doc(
params={
'server': 'Which server to collect data from when in' +
' multi-agent mode',
'name': 'Client name',
'backup': 'Backup number',
},
)
class AsyncClientTreeAll(Resource):
"""The :class:`burpui.api.async.AsyncClientTreeAll` resource allows you to
retrieve a list of all the files in a given backup through the celery
worker.
This resource is part of the :mod:`burpui.api.client` module.
An optional ``GET`` parameter called ``serverName`` is supported when
running in multi-agent mode.
"""
parser = ns.parser()
parser.add_argument(
'serverName',
help='Which server to collect data from when in multi-agent mode'
)
@ns.expect(parser)
@ns.doc(
responses={
202: 'Accepted',
405: 'Method not allowed',
403: 'Insufficient permissions',
500: 'Internal failure',
},
)
def post(self, server=None, name=None, backup=None):
"""Launch the tasks that will gather all nodes of a given backup
**POST** method provided by the webservice.
This method returns a :mod:`flask.Response` object.
:param server: Which server to collect data from when in multi-agent
mode
:type server: str
:param name: The client we are working on
:type name: str
:param backup: The backup we are working on
:type backup: int
"""
args = self.parser.parse_args()
server = server or args.get('serverName')
if not bui.client.get_attr('batch_list_supported', False, server):
self.abort(
405,
'Sorry, the requested backend does not support this method'
)
# Manage ACL
if (bui.acl and
(not bui.acl.is_client_allowed(self.username,
name,
server) and not
self.is_admin)):
self.abort(403, 'Sorry, you are not allowed to view this client')
task = load_all_tree.apply_async(
args=[
name,
backup,
server,
self.username
]
)
return {'id': task.id, 'name': 'load_all_tree'}, 202
@ns.route('/browse-status/<task_id>', endpoint='async_browse_status')
@ns.doc(
params={
'task_id': 'The task ID to process',
}
)
class AsyncBrowseStatus(Resource):
"""The :class:`burpui.api.async.AsyncBrowseStatus` resource allows you to
follow a browse task.
This resource is part of the :mod:`burpui.api.async` module.
"""
@ns.doc(
responses={
200: 'Success',
500: 'Task failed',
},
)
def get(self, task_id):
"""Returns the state of the given task"""
task = load_all_tree.AsyncResult(task_id)
if task.state == 'FAILURE':
task.revoke()
err = str(task.result)
self.abort(502, err)
if task.state == 'SUCCESS':
if not task.result:
self.abort(500, 'The task did not return anything')
server = task.result.get('server')
return {
'state': task.state,
'location': url_for(
'.async_do_browse_all',
task_id=task_id,
server=server
)
}
return {'state': task.state}
@ns.route('/get-browse/<task_id>',
'/<server>/get-browse/<task_id>',
endpoint='async_do_browse_all')
@ns.doc(
params={
'task_id': 'The task ID to process',
}
)
class AsyncDoBrowseAll(Resource):
"""The :class:`burpui.api.async.AsyncDoBrowseAll` resource allows you to
retrieve the tree generated by the given task.
This resource is part of the :mod:`burpui.api.async` module.
"""
@ns.marshal_list_with(node_fields, code=200, description='Success')
@ns.doc(
responses={
400: 'Incomplete task',
403: 'Insufficient permissions',
500: 'Task failed',
},
)
def get(self, task_id, server=None):
"""Returns the generated archive"""
task = load_all_tree.AsyncResult(task_id)
if task.state != 'SUCCESS':
if task.state == 'FAILURE':
self.abort(
500,
'Unsuccessful task: {}'.format(task.result.get('error'))
)
self.abort(400, 'Task not processed yet: {}'.format(task.state))
user = task.result.get('user')
dst_server = task.result.get('server')
resp = task.result.get('tree')
if self.username != user or (dst_server and dst_server != server):
self.abort(403, 'Unauthorized access')
task.revoke()
return resp