# luks.py # Device format classes for anaconda's storage configuration module. # # Copyright (C) 2009 Red Hat, Inc. # # This copyrighted material is made available to anyone wishing to use, # modify, copy, or redistribute it subject to the terms and conditions of # the GNU General Public License v.2, or (at your option) any later version. # This program is distributed in the hope that it will be useful, but WITHOUT # ANY WARRANTY expressed or implied, including the implied warranties 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. Any Red Hat trademarks that are incorporated in the # source code or documentation are not subject to the GNU General Public # License and may only be used or replicated with the express permission of # Red Hat, Inc. # # Red Hat Author(s): Dave Lehman # import os try: import volume_key except ImportError: volume_key = None from ..storage_log import log_method_call from ..errors import * from ..devicelibs import crypto from . import DeviceFormat, register_device_format import gettext _ = lambda x: gettext.ldgettext("anaconda", x) import logging log = logging.getLogger("storage") class LUKS(DeviceFormat): """ A LUKS device. """ _type = "luks" _name = "LUKS" _lockedName = _("Encrypted") _udevTypes = ["crypto_LUKS"] _formattable = True # can be formatted _supported = False # is supported _linuxNative = True # for clearpart _packages = ["cryptsetup-luks"] # required packages def __init__(self, *args, **kwargs): """ Create a LUKS instance. Keyword Arguments: device -- the path to the underlying device name -- the name of the mapped device uuid -- this device's UUID passphrase -- device passphrase (string) key_file -- path to a file containing a key (string) cipher -- cipher mode string key_size -- key size in bits exists -- indicates whether this is an existing format escrow_cert -- certificate to use for key escrow add_backup_passphrase -- generate a backup passphrase? """ log_method_call(self, *args, **kwargs) DeviceFormat.__init__(self, *args, **kwargs) self.cipher = kwargs.get("cipher") self.key_size = kwargs.get("key_size") self.mapName = kwargs.get("name") if not self.exists and not self.cipher: self.cipher = "aes-xts-plain64" if not self.key_size: # default to the max (512 bits) for aes-xts self.key_size = 512 # FIXME: these should both be lists, but managing them will be a pain self.__passphrase = kwargs.get("passphrase") self._key_file = kwargs.get("key_file") self.escrow_cert = kwargs.get("escrow_cert") self.add_backup_passphrase = kwargs.get("add_backup_passphrase", False) if not self.mapName and self.exists and self.uuid: self.mapName = "luks-%s" % self.uuid elif not self.mapName and self.device: self.mapName = "luks-%s" % os.path.basename(self.device) def __repr__(self): s = DeviceFormat.__repr__(self) if self.__passphrase: passphrase = "(set)" else: passphrase = "(not set)" s += (" cipher = %(cipher)s keySize = %(keySize)s" " mapName = %(mapName)s\n" " keyFile = %(keyFile)s passphrase = %(passphrase)s\n" " escrowCert = %(escrowCert)s addBackup = %(backup)s" % {"cipher": self.cipher, "keySize": self.key_size, "mapName": self.mapName, "keyFile": self._key_file, "passphrase": passphrase, "escrowCert": self.escrow_cert, "backup": self.add_backup_passphrase}) return s @property def dict(self): d = super(LUKS, self).dict d.update({"cipher": self.cipher, "keySize": self.key_size, "mapName": self.mapName, "hasKey": self.hasKey, "escrowCert": self.escrow_cert, "backup": self.add_backup_passphrase}) return d @property def name(self): name = self._name # for existing locked devices, show "Encrypted" instead of LUKS if self.hasKey or not self.exists: name = self._name else: name = "%s (%s)" % (self._lockedName, self._name) return name def _setPassphrase(self, passphrase): """ Set the passphrase used to access this device. """ self.__passphrase = passphrase passphrase = property(fset=_setPassphrase) @property def hasKey(self): return ((self.__passphrase not in ["", None]) or (self._key_file and os.access(self._key_file, os.R_OK))) @property def configured(self): """ To be ready we need a key or passphrase and a map name. """ return self.hasKey and self.mapName @property def status(self): if not self.exists or not self.mapName: return False return os.path.exists("/dev/mapper/%s" % self.mapName) def probe(self): """ Probe for any missing information about this format. cipher mode, key size """ raise NotImplementedError("probe method not defined for LUKS") def setup(self, *args, **kwargs): """ Open, or set up, the format. """ log_method_call(self, device=self.device, mapName=self.mapName, type=self.type, status=self.status) if not self.configured: raise LUKSError("luks device not configured") if self.status: return DeviceFormat.setup(self, *args, **kwargs) crypto.luks_open(self.device, self.mapName, passphrase=self.__passphrase, key_file=self._key_file) def teardown(self, *args, **kwargs): """ Close, or tear down, the format. """ log_method_call(self, device=self.device, type=self.type, status=self.status) if not self.exists: raise LUKSError("format has not been created") if self.status: log.debug("unmapping %s" % self.mapName) crypto.luks_close(self.mapName) def create(self, *args, **kwargs): """ Create the format. """ log_method_call(self, device=self.device, type=self.type, status=self.status) if not self.hasKey: raise LUKSError("luks device has no key/passphrase") try: DeviceFormat.create(self, *args, **kwargs) crypto.luks_format(self.device, passphrase=self.__passphrase, key_file=self._key_file, cipher=self.cipher, key_size=self.key_size) except Exception: raise else: self.uuid = crypto.luks_uuid(self.device) self.exists = True self.mapName = "luks-%s" % self.uuid self.notifyKernel() def destroy(self, *args, **kwargs): """ Create the format. """ log_method_call(self, device=self.device, type=self.type, status=self.status) self.teardown() DeviceFormat.destroy(self, *args, **kwargs) @property def keyFile(self): """ Path to key file to be used in /etc/crypttab """ return self._key_file def addKeyFromFile(self, keyfile): """ Add a new key from a file. Add the contents of the specified key file to an available key slot in the LUKS header. """ log_method_call(self, device=self.device, type=self.type, status=self.status, file=keyfile) if not self.exists: raise LUKSError("format has not been created") crypto.luks_add_key(self.device, passphrase=self.__passphrase, key_file=self._key_file, new_key_file=keyfile) def addPassphrase(self, passphrase): """ Add a new passphrase. Add the specified passphrase to an available key slot in the LUKS header. """ log_method_call(self, device=self.device, type=self.type, status=self.status) if not self.exists: raise LUKSError("format has not been created") crypto.luks_add_key(self.device, passphrase=self.__passphrase, key_file=self._key_file, new_passphrase=passphrase) def removeKeyFromFile(self, keyfile): """ Remove a key contained in a file. Remove key contained in the specified key file from the LUKS header. """ log_method_call(self, device=self.device, type=self.type, status=self.status, file=keyfile) if not self.exists: raise LUKSError("format has not been created") crypto.luks_remove_key(self.device, passphrase=self.__passphrase, key_file=self._key_file, del_key_file=keyfile) def removePassphrase(self, passphrase): """ Remove the specified passphrase from the LUKS header. """ log_method_call(self, device=self.device, type=self.type, status=self.status) if not self.exists: raise LUKSError("format has not been created") crypto.luks_remove_key(self.device, passphrase=self.__passphrase, key_file=self._key_file, del_passphrase=passphrase) def _escrowVolumeIdent(self, vol): """ Return an escrow packet filename prefix for a volume_key.Volume. """ label = vol.label if label is not None: label = label.replace("/", "_") uuid = vol.uuid if uuid is not None: uuid = uuid.replace("/", "_") # uuid is never None on LUKS volumes if label is not None and uuid is not None: volume_ident = "%s-%s" % (label, uuid) elif uuid is not None: volume_ident = uuid elif label is not None: volume_ident = label else: volume_ident = "_unknown" return volume_ident def escrow(self, directory, backupPassphrase): log.debug("escrow: escrowVolume start for %s" % self.device) if volume_key is None: raise LUKSError("Missing key escrow support libraries") vol = volume_key.Volume.open(self.device) volume_ident = self._escrowVolumeIdent(vol) ui = volume_key.UI() # This callback is not expected to be used, let it always fail ui.generic_cb = lambda unused_prompt, unused_echo: None def known_passphrase_cb(unused_prompt, failed_attempts): if failed_attempts == 0: return self.__passphrase return None ui.passphrase_cb = known_passphrase_cb log.debug("escrow: getting secret") vol.get_secret(volume_key.SECRET_DEFAULT, ui) log.debug("escrow: creating packet") default_packet = vol.create_packet_assymetric_from_cert_data \ (volume_key.SECRET_DEFAULT, self.escrow_cert, ui) log.debug("escrow: packet created") with open("%s/%s-escrow" % (directory, volume_ident), "wb") as f: f.write(default_packet) log.debug("escrow: packet written") if self.add_backup_passphrase: log.debug("escrow: adding backup passphrase") vol.add_secret(volume_key.SECRET_PASSPHRASE, backupPassphrase) log.debug("escrow: creating backup packet") backup_passphrase_packet = \ vol.create_packet_assymetric_from_cert_data \ (volume_key.SECRET_PASSPHRASE, self.escrow_cert, ui) log.debug("escrow: backup packet created") with open("%s/%s-escrow-backup-passphrase" % (directory, volume_ident), "wb") as f: f.write(backup_passphrase_packet) log.debug("escrow: backup packet written") log.debug("escrow: escrowVolume done for %s" % repr(self.device)) register_device_format(LUKS)