core-admin/qubes/app.py
Wojtek Porczyk 6ade5736d7 pylint fixes
2016-06-10 21:27:29 +02:00

1025 lines
32 KiB
Python

#!/usr/bin/python2 -O
# vim: fileencoding=utf-8
#
# The Qubes OS Project, https://www.qubes-os.org/
#
# Copyright (C) 2010-2015 Joanna Rutkowska <joanna@invisiblethingslab.com>
# Copyright (C) 2011-2015 Marek Marczykowski-Górecki
# <marmarek@invisiblethingslab.com>
# Copyright (C) 2014-2015 Wojtek Porczyk <woju@invisiblethingslab.com>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
#
import collections
import errno
import functools
import grp
import logging
import os
import random
import sys
import tempfile
import time
import uuid
import jinja2
import lxml.etree
import libvirt
try:
import xen.lowlevel.xs
import xen.lowlevel.xc
except ImportError:
pass
if os.name == 'posix':
# pylint: disable=wrong-import-order
import fcntl
elif os.name == 'nt':
# pylint: disable=import-error
import win32con
import win32file
import pywintypes
else:
raise RuntimeError("Qubes works only on POSIX or WinNT systems")
import qubes
import qubes.ext
import qubes.utils
import qubes.vm.adminvm
import qubes.vm.qubesvm
import qubes.vm.templatevm
class VirDomainWrapper(object):
# pylint: disable=too-few-public-methods
def __init__(self, connection, vm):
self._connection = connection
self._vm = vm
def _reconnect_if_dead(self):
is_dead = not self._vm.connect().isAlive()
if is_dead:
# pylint: disable=protected-access
self._connection._reconnect_if_dead()
self._vm = self._connection._conn.lookupByUUID(self._vm.getUUID())
return is_dead
def __getattr__(self, attrname):
attr = getattr(self._vm, attrname)
if not isinstance(attr, collections.Callable):
return attr
@functools.wraps(attr)
def wrapper(*args, **kwargs):
try:
return attr(*args, **kwargs)
except libvirt.libvirtError:
if self._reconnect_if_dead():
return getattr(self._vm, attrname)(*args, **kwargs)
raise
return wrapper
class VirConnectWrapper(object):
# pylint: disable=too-few-public-methods
def __init__(self, uri):
self._conn = libvirt.open(uri)
def _reconnect_if_dead(self):
is_dead = not self._conn.isAlive()
if is_dead:
self._conn = libvirt.open(self._conn.getURI())
return is_dead
def _wrap_domain(self, ret):
if isinstance(ret, libvirt.virDomain):
ret = VirDomainWrapper(self, ret)
return ret
def __getattr__(self, attrname):
attr = getattr(self._conn, attrname)
if not isinstance(attr, collections.Callable):
return attr
@functools.wraps(attr)
def wrapper(*args, **kwargs):
try:
return self._wrap_domain(attr(*args, **kwargs))
except libvirt.libvirtError:
if self._reconnect_if_dead():
return self._wrap_domain(
getattr(self._conn, attrname)(*args, **kwargs))
raise
return wrapper
class VMMConnection(object):
'''Connection to Virtual Machine Manager (libvirt)'''
def __init__(self, offline_mode=False):
self._libvirt_conn = None
self._xs = None
self._xc = None
self._offline_mode = offline_mode
@property
def offline_mode(self):
'''Check or enable offline mode (do not actually connect to vmm)'''
return self._offline_mode
def _libvirt_error_handler(self, ctx, error):
pass
def init_vmm_connection(self):
'''Initialise connection
This method is automatically called when getting'''
if self._libvirt_conn is not None:
# Already initialized
return
if self._offline_mode:
# Do not initialize in offline mode
raise qubes.exc.QubesException(
'VMM operations disabled in offline mode')
if 'xen.lowlevel.xs' in sys.modules:
self._xs = xen.lowlevel.xs.xs()
if 'xen.lowlevel.cs' in sys.modules:
self._xc = xen.lowlevel.xc.xc()
self._libvirt_conn = VirConnectWrapper(
qubes.config.defaults['libvirt_uri'])
libvirt.registerErrorHandler(self._libvirt_error_handler, None)
@property
def libvirt_conn(self):
'''Connection to libvirt'''
self.init_vmm_connection()
return self._libvirt_conn
@property
def xs(self):
'''Connection to Xen Store
This property in available only when running on Xen.
'''
# XXX what about the case when we run under KVM,
# but xen modules are importable?
if 'xen.lowlevel.xs' not in sys.modules:
raise AttributeError(
'xs object is available under Xen hypervisor only')
self.init_vmm_connection()
return self._xs
@property
def xc(self):
'''Connection to Xen
This property in available only when running on Xen.
'''
# XXX what about the case when we run under KVM,
# but xen modules are importable?
if 'xen.lowlevel.xc' not in sys.modules:
raise AttributeError(
'xc object is available under Xen hypervisor only')
self.init_vmm_connection()
return self._xs
def __del__(self):
if self._libvirt_conn:
self._libvirt_conn.close()
class QubesHost(object):
'''Basic information about host machine
:param qubes.Qubes app: Qubes application context (must have \
:py:attr:`Qubes.vmm` attribute defined)
'''
def __init__(self, app):
self.app = app
self._no_cpus = None
self._total_mem = None
self._physinfo = None
def _fetch(self):
if self._no_cpus is not None:
return
# pylint: disable=unused-variable
(model, memory, cpus, mhz, nodes, socket, cores, threads) = \
self.app.vmm.libvirt_conn.getInfo()
self._total_mem = long(memory) * 1024
self._no_cpus = cpus
self.app.log.debug('QubesHost: no_cpus={} memory_total={}'.format(
self.no_cpus, self.memory_total))
try:
self.app.log.debug('QubesHost: xen_free_memory={}'.format(
self.get_free_xen_memory()))
except NotImplementedError:
pass
@property
def memory_total(self):
'''Total memory, in kbytes'''
self._fetch()
return self._total_mem
@property
def no_cpus(self):
'''Number of CPUs'''
self._fetch()
return self._no_cpus
def get_free_xen_memory(self):
'''Get free memory from Xen's physinfo.
:raises NotImplementedError: when not under Xen
'''
try:
self._physinfo = self.app.xc.physinfo()
except AttributeError:
raise NotImplementedError('This function requires Xen hypervisor')
return long(self._physinfo['free_memory'])
def measure_cpu_usage(self, previous_time=None, previous=None,
wait_time=1):
'''Measure cpu usage for all domains at once.
This function requires Xen hypervisor.
.. versionchanged:: 3.0
argument order to match return tuple
:raises NotImplementedError: when not under Xen
'''
if previous is None:
previous_time = time.time()
previous = {}
try:
info = self.app.vmm.xc.domain_getinfo(0, qubes.config.max_qid)
except AttributeError:
raise NotImplementedError(
'This function requires Xen hypervisor')
for vm in info:
previous[vm['domid']] = {}
previous[vm['domid']]['cpu_time'] = (
vm['cpu_time'] / vm['online_vcpus'])
previous[vm['domid']]['cpu_usage'] = 0
time.sleep(wait_time)
current_time = time.time()
current = {}
try:
info = self.app.vmm.xc.domain_getinfo(0, qubes.config.max_qid)
except AttributeError:
raise NotImplementedError(
'This function requires Xen hypervisor')
for vm in info:
current[vm['domid']] = {}
current[vm['domid']]['cpu_time'] = (
vm['cpu_time'] / max(vm['online_vcpus'], 1))
if vm['domid'] in previous.keys():
current[vm['domid']]['cpu_usage'] = (
float(current[vm['domid']]['cpu_time'] -
previous[vm['domid']]['cpu_time']) /
long(1000 ** 3) / (current_time - previous_time) * 100)
if current[vm['domid']]['cpu_usage'] < 0:
# VM has been rebooted
current[vm['domid']]['cpu_usage'] = 0
else:
current[vm['domid']]['cpu_usage'] = 0
return (current_time, current)
class VMCollection(object):
'''A collection of Qubes VMs
VMCollection supports ``in`` operator. You may test for ``qid``, ``name``
and whole VM object's presence.
Iterating over VMCollection will yield machine objects.
'''
def __init__(self, app):
self.app = app
self._dict = dict()
def __repr__(self):
return '<{} {!r}>'.format(
self.__class__.__name__, list(sorted(self.keys())))
def items(self):
'''Iterate over ``(qid, vm)`` pairs'''
for qid in self.qids():
yield (qid, self[qid])
def qids(self):
'''Iterate over all qids
qids are sorted by numerical order.
'''
return iter(sorted(self._dict.keys()))
keys = qids
def names(self):
'''Iterate over all names
names are sorted by lexical order.
'''
return iter(sorted(vm.name for vm in self._dict.values()))
def vms(self):
'''Iterate over all machines
vms are sorted by qid.
'''
return iter(sorted(self._dict.values()))
__iter__ = vms
values = vms
def add(self, value, _enable_events=True):
'''Add VM to collection
:param qubes.vm.BaseVM value: VM to add
:raises TypeError: when value is of wrong type
:raises ValueError: when there is already VM which has equal ``qid``
'''
# this violates duck typing, but is needed
# for VMProperty to function correctly
if not isinstance(value, qubes.vm.BaseVM):
raise TypeError('{} holds only BaseVM instances'.format(
self.__class__.__name__))
if value.qid in self:
raise ValueError('This collection already holds VM that has '
'qid={!r} ({!r})'.format(value.qid, self[value.qid]))
if value.name in self:
raise ValueError('This collection already holds VM that has '
'name={!r} ({!r})'.format(value.name, self[value.name]))
self._dict[value.qid] = value
if _enable_events:
value.events_enabled = True
self.app.fire_event('domain-add', value)
return value
def __getitem__(self, key):
if isinstance(key, int):
return self._dict[key]
if isinstance(key, basestring):
for vm in self:
if vm.name == key:
return vm
raise KeyError(key)
if isinstance(key, qubes.vm.BaseVM):
key = key.uuid
if isinstance(key, uuid.UUID):
for vm in self:
if vm.uuid == key:
return vm
raise KeyError(key)
raise KeyError(key)
def __delitem__(self, key):
vm = self[key]
self.app.fire_event_pre('domain-pre-delete', vm)
del self._dict[vm.qid]
self.app.fire_event('domain-delete', vm)
def __contains__(self, key):
return any((key == vm or key == vm.qid or key == vm.name)
for vm in self)
def __len__(self):
return len(self._dict)
def get_vms_based_on(self, template):
template = self[template]
return set(vm for vm in self
if hasattr(vm, 'template') and vm.template == template)
def get_vms_connected_to(self, netvm):
new_vms = set([self[netvm]])
dependent_vms = set()
# Dependency resolving only makes sense on NetVM (or derivative)
# if not self[netvm_qid].is_netvm():
# return set([])
while len(new_vms) > 0:
cur_vm = new_vms.pop()
for vm in cur_vm.connected_vms:
if vm in dependent_vms:
continue
dependent_vms.add(vm.qid)
# if vm.is_netvm():
new_vms.add(vm.qid)
return dependent_vms
# XXX with Qubes Admin Api this will probably lead to race condition
# whole process of creating and adding should be synchronised
def get_new_unused_qid(self):
used_ids = set(self.qids())
for i in range(1, qubes.config.max_qid):
if i not in used_ids:
return i
raise LookupError("Cannot find unused qid!")
def get_new_unused_netid(self):
used_ids = set([vm.netid for vm in self]) # if vm.is_netvm()])
for i in range(1, qubes.config.max_netid):
if i not in used_ids:
return i
raise LookupError("Cannot find unused netid!")
def get_new_unused_dispid(self):
for _ in range(qubes.config.max_dispid ** 0.5):
dispid = random.SystemRandom().randrange(qubes.config.max_dispid)
if not any(getattr(vm, 'dispid', None) == dispid for vm in self):
return dispid
raise LookupError((
'https://xkcd.com/221/',
'http://dilbert.com/strip/2001-10-25')[random.randint(0, 1)])
class Qubes(qubes.PropertyHolder):
'''Main Qubes application
:param str store: path to ``qubes.xml``
The store is loaded in stages:
1. In the first stage there are loaded some basic features from store
(currently labels).
2. In the second stage stubs for all VMs are loaded. They are filled
with their basic properties, like ``qid`` and ``name``.
3. In the third stage all global properties are loaded. They often
reference VMs, like default netvm, so they should be filled after
loading VMs.
4. In the fourth stage all remaining VM properties are loaded. They
also need all VMs loaded, because they represent dependencies
between VMs like aforementioned netvm.
5. In the fifth stage there are some fixups to ensure sane system
operation.
This class emits following events:
.. event:: domain-add (subject, event, vm)
When domain is added.
:param subject: Event emitter
:param event: Event name (``'domain-add'``)
:param vm: Domain object
.. event:: domain-delete (subject, event, vm)
When domain is deleted. VM still has reference to ``app`` object,
but is not contained within VMCollection.
:param subject: Event emitter
:param event: Event name (``'domain-delete'``)
:param vm: Domain object
Methods and attributes:
'''
default_netvm = qubes.VMProperty('default_netvm', load_stage=3,
default=None, allow_none=True,
doc='''Default NetVM for AppVMs. Initial state is `None`, which means
that AppVMs are not connected to the Internet.''')
default_fw_netvm = qubes.VMProperty('default_fw_netvm', load_stage=3,
default=None, allow_none=True,
doc='''Default NetVM for ProxyVMs. Initial state is `None`, which means
that ProxyVMs (including FirewallVM) are not connected to the
Internet.''')
default_template = qubes.VMProperty('default_template', load_stage=3,
vmclass=qubes.vm.templatevm.TemplateVM,
doc='Default template for new AppVMs')
updatevm = qubes.VMProperty('updatevm', load_stage=3,
allow_none=True,
doc='''Which VM to use as `yum` proxy for updating AdminVM and
TemplateVMs''')
clockvm = qubes.VMProperty('clockvm', load_stage=3,
allow_none=True,
doc='Which VM to use as NTP proxy for updating AdminVM')
default_kernel = qubes.property('default_kernel', load_stage=3,
doc='Which kernel to use when not overriden in VM')
# TODO #1637 #892
check_updates_vm = qubes.property('check_updates_vm',
type=bool, setter=qubes.property.bool,
default=True,
doc='check for updates inside qubes')
def __init__(self, store=None, load=True, offline_mode=False, **kwargs):
#: logger instance for logging global messages
self.log = logging.getLogger('app')
self._extensions = qubes.ext.get_extensions()
#: collection of all VMs managed by this Qubes instance
self.domains = VMCollection(self)
#: collection of all available labels for VMs
self.labels = {}
#: collection of all pools
self.pools = {}
#: Connection to VMM
self.vmm = VMMConnection(offline_mode=offline_mode)
#: Information about host system
self.host = QubesHost(self)
if store is not None:
self._store = store
else:
self._store = os.environ.get('QUBES_XML_PATH',
os.path.join(
qubes.config.system_path['qubes_base_dir'],
qubes.config.system_path['qubes_store_filename']))
super(Qubes, self).__init__(xml=None, **kwargs)
self.__load_timestamp = None
#: jinja2 environment for libvirt XML templates
self.env = jinja2.Environment(
loader=jinja2.FileSystemLoader('/usr/share/qubes/templates'),
undefined=jinja2.StrictUndefined)
if load:
self.load()
self.events_enabled = True
@property
def store(self):
return self._store
def load(self):
'''Open qubes.xml
:throws EnvironmentError: failure on parsing store
:throws xml.parsers.expat.ExpatError: failure on parsing store
:raises lxml.etree.XMLSyntaxError: on syntax error in qubes.xml
'''
try:
fd = os.open(self._store, os.O_RDWR) # no O_CREAT
except OSError as e:
if e.errno != errno.ENOENT:
raise
raise qubes.exc.QubesException(
'Qubes XML store {!r} is missing; use qubes-create tool'.format(
self._store))
fh = os.fdopen(fd, 'rb')
if os.name == 'posix':
fcntl.lockf(fh, fcntl.LOCK_EX)
elif os.name == 'nt':
# pylint: disable=protected-access
win32file.LockFileEx(
win32file._get_osfhandle(fh.fileno()),
win32con.LOCKFILE_EXCLUSIVE_LOCK,
0, -0x10000,
pywintypes.OVERLAPPED())
self.xml = lxml.etree.parse(fh)
# stage 1: load labels and pools
for node in self.xml.xpath('./labels/label'):
label = qubes.Label.fromxml(node)
self.labels[label.index] = label
for node in self.xml.xpath('./pools/pool'):
name = node.get('name')
assert name, "Pool name '%s' is invalid " % name
try:
self.pools[name] = self._get_pool(**node.attrib)
except qubes.exc.QubesException as e:
self.log.error(e.message)
# stage 2: load VMs
for node in self.xml.xpath('./domains/domain'):
# pylint: disable=no-member
cls = self.get_vm_class(node.get('class'))
vm = cls(self, node)
vm.load_properties(load_stage=2)
vm.init_log()
self.domains.add(vm, _enable_events=False)
if 0 not in self.domains:
self.domains.add(
qubes.vm.adminvm.AdminVM(self, None, qid=0, name='dom0'),
_enable_events=False)
# stage 3: load global properties
self.load_properties(load_stage=3)
# stage 4: fill all remaining VM properties
for vm in self.domains:
vm.load_properties(load_stage=4)
# stage 5: misc fixups
self.property_require('default_fw_netvm', allow_none=True)
self.property_require('default_netvm', allow_none=True)
self.property_require('default_template')
self.property_require('clockvm', allow_none=True)
self.property_require('updatevm', allow_none=True)
# Disable ntpd in ClockVM - to not conflict with ntpdate (both are
# using 123/udp port)
if hasattr(self, 'clockvm') and self.clockvm is not None:
if self.clockvm.features.get('services/ntpd', False):
self.log.warning(
'VM set as clockvm (%r) has enabled \'ntpd\' service! '
'Expect failure when syncing time in dom0.',
self.clockvm)
else:
self.clockvm.features['services/ntpd'] = ''
for vm in self.domains:
vm.events_enabled = True
vm.fire_event('domain-load')
# get a file timestamp (before closing it - still holding the lock!),
# to detect whether anyone else have modified it in the meantime
self.__load_timestamp = os.path.getmtime(self._store)
# intentionally do not call explicit unlock
fh.close()
del fh
def __xml__(self):
element = lxml.etree.Element('qubes')
element.append(self.xml_labels())
pools_xml = lxml.etree.Element('pools')
for pool in self.pools.values():
xml = pool.__xml__()
if xml is not None:
pools_xml.append(xml)
element.append(pools_xml)
element.append(self.xml_properties())
domains = lxml.etree.Element('domains')
for vm in self.domains:
domains.append(vm.__xml__())
element.append(domains)
return element
def save(self):
'''Save all data to qubes.xml
There are several problems with saving :file:`qubes.xml` which must be
mitigated:
- Running out of disk space. No space left should not result in empty
file. This is done by writing to temporary file and then renaming.
- Attempts to write two or more files concurrently. This is done by
sophisticated locking.
:throws EnvironmentError: failure on saving
'''
while True:
fd_old = os.open(self._store, os.O_RDWR | os.O_CREAT)
if os.name == 'posix':
fcntl.lockf(fd_old, fcntl.LOCK_EX)
elif os.name == 'nt':
# pylint: disable=protected-access
overlapped = pywintypes.OVERLAPPED()
win32file.LockFileEx(
win32file._get_osfhandle(fd_old),
win32con.LOCKFILE_EXCLUSIVE_LOCK, 0, -0x10000, overlapped)
# While we were waiting for lock, someone could have unlink()ed (or
# rename()d) our file out of the filesystem. We have to ensure we
# got lock on something linked to filesystem. If not, try again.
if os.fstat(fd_old) == os.stat(self._store):
break
else:
os.close(fd_old)
if self.__load_timestamp:
current_file_timestamp = os.path.getmtime(self._store)
if current_file_timestamp != self.__load_timestamp:
os.close(fd_old)
raise qubes.exc.QubesException(
"Someone else modified qubes.xml in the meantime")
fh_new = tempfile.NamedTemporaryFile(prefix=self._store, delete=False)
lxml.etree.ElementTree(self.__xml__()).write(
fh_new, encoding='utf-8', pretty_print=True)
fh_new.flush()
os.chmod(fh_new.name, 0660)
os.chown(fh_new.name, -1, grp.getgrnam('qubes').gr_gid)
os.rename(fh_new.name, self._store)
# intentionally do not call explicit unlock to not unlock the file
# before all buffers are flushed
fh_new.close()
# update stored mtime, in case of multiple save() calls without
# loading qubes.xml again
self.__load_timestamp = os.path.getmtime(self._store)
os.close(fd_old)
def load_initial_values(self):
self.labels = {
1: qubes.Label(1, '0xcc0000', 'red'),
2: qubes.Label(2, '0xf57900', 'orange'),
3: qubes.Label(3, '0xedd400', 'yellow'),
4: qubes.Label(4, '0x73d216', 'green'),
5: qubes.Label(5, '0x555753', 'gray'),
6: qubes.Label(6, '0x3465a4', 'blue'),
7: qubes.Label(7, '0x75507b', 'purple'),
8: qubes.Label(8, '0x000000', 'black'),
}
for name, config in qubes.config.defaults['pool_configs'].items():
self.pools[name] = self._get_pool(**config)
self.domains.add(
qubes.vm.adminvm.AdminVM(self, None, qid=0, name='dom0'))
@classmethod
def create_empty_store(cls, *args, **kwargs):
self = cls(*args, load=False, **kwargs)
self.load_initial_values()
self.save()
return self
def xml_labels(self):
'''Serialise labels
:rtype: lxml.etree._Element
'''
labels = lxml.etree.Element('labels')
for label in sorted(self.labels.values(), key=lambda labl: labl.index):
labels.append(label.__xml__())
return labels
@staticmethod
def get_vm_class(clsname):
'''Find the class for a domain.
Classess are registered as setuptools' entry points in ``qubes.vm``
group. Any package may supply their own classess.
:param str clsname: name of the class
:return type: class
'''
try:
return qubes.utils.get_entry_point_one('qubes.vm', clsname)
except KeyError:
raise qubes.exc.QubesException(
'no such VM class: {!r}'.format(clsname))
# don't catch TypeError
def add_new_vm(self, cls, qid=None, **kwargs):
'''Add new Virtual Machine to colletion
'''
if qid is None:
qid = self.domains.get_new_unused_qid()
# handle default template; specifically allow template=None (do not
# override it with default template)
if 'template' not in kwargs and hasattr(cls, 'template'):
kwargs['template'] = self.default_template
return self.domains.add(cls(self, None, qid=qid, **kwargs))
def get_label(self, label):
'''Get label as identified by index or name
:throws KeyError: when label is not found
'''
# first search for index, verbatim
try:
return self.labels[label]
except KeyError:
pass
# then search for name
for i in self.labels.values():
if i.name == label:
return i
# last call, if label is a number represented as str, search in indices
try:
return self.labels[int(label)]
except (KeyError, ValueError):
pass
raise KeyError(label)
def add_pool(self, name, **kwargs):
""" Add a storage pool to config."""
if name in self.pools.keys():
raise qubes.exc.QubesException('pool named %s already exists \n' %
name)
kwargs['name'] = name
pool = self._get_pool(**kwargs)
pool.setup()
self.pools[name] = pool
def remove_pool(self, name):
""" Remove a storage pool from config file. """
try:
pool = self.pools[name]
del self.pools[name]
pool.destroy()
except KeyError:
return
def get_pool(self, name):
''' Returns a :py:class:`qubes.storage.Pool` instance '''
try:
return self.pools[name]
except KeyError:
raise qubes.exc.QubesException('Unknown storage pool ' + name)
@staticmethod
def _get_pool(**kwargs):
try:
name = kwargs['name']
assert name, 'Name needs to be an non empty string'
except KeyError:
raise qubes.exc.QubesException('No pool name for pool')
try:
driver = kwargs['driver']
except KeyError:
raise qubes.exc.QubesException('No driver specified for pool ' +
name)
try:
klass = qubes.utils.get_entry_point_one(
qubes.storage.STORAGE_ENTRY_POINT, driver)
del kwargs['driver']
return klass(**kwargs)
except KeyError:
raise qubes.exc.QubesException('No driver %s for pool %s' %
(driver, name))
@qubes.events.handler('domain-pre-delete')
def on_domain_pre_deleted(self, event, vm):
# pylint: disable=unused-argument
if isinstance(vm, qubes.vm.templatevm.TemplateVM):
appvms = self.domains.get_vms_based_on(vm)
if appvms:
raise qubes.exc.QubesException(
'Cannot remove template that has dependent AppVMs. '
'Affected are: {}'.format(', '.join(
vm.name for name in sorted(appvms))))
@qubes.events.handler('domain-delete')
def on_domain_deleted(self, event, vm):
# pylint: disable=unused-argument
for propname in (
'default_netvm',
'default_fw_netvm',
'clockvm',
'updatevm',
'default_template',
):
try:
if getattr(self, propname) == vm:
delattr(self, propname)
except AttributeError:
pass
@qubes.events.handler('property-pre-set:clockvm')
def on_property_pre_set_clockvm(self, event, name, newvalue, oldvalue=None):
# pylint: disable=unused-argument,no-self-use
if newvalue is None:
return
if newvalue.features.get('services/ntpd', False):
raise qubes.exc.QubesVMError(newvalue,
'Cannot set {!r} as {!r} since it has ntpd enabled.'.format(
newvalue.name, name))
else:
newvalue.features['services/ntpd'] = ''
@qubes.events.handler(
'property-pre-set:default_netvm',
'property-pre-set:default_fw_netvm')
def on_property_pre_set_default_netvm(self, event, name, newvalue,
oldvalue=None):
# pylint: disable=unused-argument,invalid-name
if newvalue is not None and oldvalue is not None \
and oldvalue.is_running() and not newvalue.is_running() \
and self.domains.get_vms_connected_to(oldvalue):
raise qubes.exc.QubesVMNotRunningError(newvalue,
'Cannot change {!r} to domain that '
'is not running ({!r}).'.format(name, newvalue.name))
@qubes.events.handler('property-set:default_fw_netvm')
def on_property_set_default_fw_netvm(self, event, name, newvalue,
oldvalue=None):
# pylint: disable=unused-argument,invalid-name
for vm in self.domains:
if not vm.provides_network and vm.property_is_default('netvm'):
# fire property-del:netvm as it is responsible for resetting
# netvm to it's default value
vm.fire_event('property-del:netvm', 'netvm', newvalue, oldvalue)
@qubes.events.handler('property-set:default_netvm')
def on_property_set_default_netvm(self, event, name, newvalue,
oldvalue=None):
# pylint: disable=unused-argument
for vm in self.domains:
if vm.provides_network and vm.property_is_default('netvm'):
# fire property-del:netvm as it is responsible for resetting
# netvm to it's default value
vm.fire_event('property-del:netvm', 'netvm', oldvalue)