959 lines
31 KiB
Python
959 lines
31 KiB
Python
#
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# Copyright 2007 sense.lab e.V.
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#
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# This file is part of the CryptoBox.
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#
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# The CryptoBox is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation; either version 2 of the License, or
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# (at your option) any later version.
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#
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# The CryptoBox is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with the CryptoBox; if not, write to the Free Software
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# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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#
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'''
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These classes detect and filter available blockdevices.
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'''
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#TODO: call blkid only once for all devices and scan the result
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__revision__ = "$Id$"
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import os
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import subprocess
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import time
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import logging
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import cryptobox.core.settings
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OPTIONAL_PROGS = { "lvm": True }
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"""remember which programs don't exist to avoid calling them in vain
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change default values from "True" to "False" to disable the respective program
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"""
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LOGGER = logging.getLogger("CryptoBox")
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DEFAULT_SYSBLOCK_DIR = '/sys/block'
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DEFAULT_DEVNODE_DIR = '/dev'
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MINIMUM_STORAGE_SIZE = 10
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MAJOR_DEVNUM_RAM = 1
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MAJOR_DEVNUM_LOOP = 7
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MAJOR_DEVNUM_MD_RAID = 9
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## cache settings
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CACHE_ENABLED = True
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CACHE_EXPIRE_SECONDS = 60
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CACHE_MONITOR_FILE = '/proc/partitions'
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## useful for manual profiling
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IS_VISIBLE = True
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## caching is quite important for the following implementation
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## the object will be initializes later below
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CACHE = None
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class Blockdevices:
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"""handle all blockdevices of this system
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"""
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def __init__(self,
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sysblock_dir=DEFAULT_SYSBLOCK_DIR,
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devnode_dir=DEFAULT_DEVNODE_DIR):
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self.sysblock_dir = sysblock_dir
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self.devnode_dir = devnode_dir
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self.devices = []
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for devdir in find_blockdevices(self.sysblock_dir):
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blockdevice = get_blockdevice(devdir,
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self.sysblock_dir, self.devnode_dir)
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if (not blockdevice is None) and blockdevice.is_valid():
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self.devices.append(blockdevice)
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def get_devices(self):
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"""return a copy of the device list
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"""
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return self.devices[:]
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def get_storage_devices(self):
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"""return a list of devices with the 'storage' flag
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"""
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return [ dev for dev in self.devices if dev.is_storage() ]
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def get_partitionable_devices(self):
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"""return a list of devices with the 'partitionable' flag
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"""
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return [ dev for dev in self.devices if dev.is_partitionable() ]
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class Blockdevice:
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def __init__(self, dev,
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sysblock_dir=DEFAULT_SYSBLOCK_DIR,
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devnode_dir=DEFAULT_DEVNODE_DIR):
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"""initialize the blockdevice
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@type dev: string
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@param dev: The /sys/block/ subdirectory describing a blockdevice
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@type sysblock_dir: string
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@param sysblock_dir: The linux /sys/ directory. Default is '/sys'.
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@type devnode_dir: string
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@param devnode_dir: The linux /dev/ directory. Default is '/dev'.
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"""
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self.devdir = dev
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self.devnode_dir = devnode_dir
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self.sysblock_dir = sysblock_dir
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self.name = os.path.basename(self.devdir)
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## "reset" below will fill these values
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self.devnum = None
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self.size = None
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self.size_human = None
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self.range = None
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self.slaves = None
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self.holders = None
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self.children = None
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self.devnodes = None
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self.uuid = None
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self.label = None
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self.reset(empty_cache=False)
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def reset(self, empty_cache=True):
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"""reread the data of the device
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usually we will have to reset the cache, too
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just in case of first-time initialization, this is not necessary
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@type empty_cache: boolean
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@param empty_cache: Whether to discard the cached information or not.
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"""
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CACHE.reset(["blockdevice_info", self.name])
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self.devnum = self.__get_major_minor()
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self.size = self.__get_size()
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self.size_human = self.__get_size_human()
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self.range = self.__get_device_range()
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self.slaves = self.__get_dev_related("slaves")
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self.holders = self.__get_dev_related("holders")
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self.children = self.__get_children()
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self.devnodes = self.__get_device_nodes()
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self.uuid = self.__get_uuid()
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self.label = self.__get_label()
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self.type_id = self.__get_type_id()
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def is_valid(self):
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"""check if the device is usable and valid
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causes of invalidity: ram device, loop device, removable device
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@rtype: boolean
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@return: 'True' for a valid blockdevice
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"""
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if not self.devnodes:
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return False
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## check valid devnum
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try:
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major, minor = self.devnum
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if (major == 0) and (minor == 0):
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return False
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## ram devices are ignored
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if major == MAJOR_DEVNUM_RAM:
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return False
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## loop devices are ignored
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if (major == MAJOR_DEVNUM_LOOP) and (self.size == 0):
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return False
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## removable devices are ignored (due to long timeouts)
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if self.is_removable():
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return False
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except TypeError:
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return False
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return True
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def is_storage(self):
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"""return if this device can be used as a storage
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@rtype: boolean
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@return: 'True' for a device usable as a storage
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"""
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## check the cache first
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cache_link = ["blockdevice_info", self.name, "is_storage"]
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cached = CACHE.get(cache_link)
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if not cached is None:
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return cached
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if self.range > 1:
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## partitionable blockdevice
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CACHE.set(cache_link, False)
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return False
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if self.size < MINIMUM_STORAGE_SIZE:
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## extended partition, unused loop device
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CACHE.set(cache_link, False)
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return False
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if self.devnum[0] == MAJOR_DEVNUM_RAM:
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## ram device
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CACHE.set(cache_link, False)
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return False
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## are we the device mapper of a luks device?
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for slave in self.slaves:
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if get_blockdevice(slave, self.sysblock_dir,
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self.devnode_dir).is_luks():
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CACHE.set(cache_link, False)
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return False
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## if we are a luks device with exactly one child, then
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## we are a storage
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if (len(self.children) == 1) and self.is_luks():
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CACHE.set(cache_link, True)
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return True
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if self.children:
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## a parent blockdevice
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CACHE.set(cache_link, False)
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return False
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CACHE.set(cache_link, True)
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return True
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def is_partitionable(self):
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"""is the device partitionable
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"""
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if self.range > 1:
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return True
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else:
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return False
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def is_lvm_pv(self):
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"""return if the device is a physical volume of a LVM
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"""
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## check the cache first
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cache_link = ["blockdevice_info", self.name, "is_lvm_pv"]
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cached = CACHE.get(cache_link)
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if not cached is None:
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return cached
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## is one of the devnodes of the device a physical volume?
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for one_lvm_pv in find_lvm_pv():
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if one_lvm_pv in self.devnodes:
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CACHE.set(cache_link, True)
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return True
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CACHE.set(cache_link, False)
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return False
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def is_lvm_lv(self):
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"""return if the device is a logical volume of a LVM
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"""
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## check the cache first
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cache_link = ["blockdevice_info", self.name, "is_lvm_lv"]
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cached = CACHE.get(cache_link)
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if not cached is None:
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return cached
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## is one of the devnodes of the device a physical volume?
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## logical LVM volumes always depend on their physical volumes
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if not self.slaves:
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CACHE.set(cache_link, False)
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return False
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## is one of the LVM physical volumes a device node of our slave(s)?
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for one_lvm_pv in find_lvm_pv():
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for one_slave in self.slaves:
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if one_lvm_pv in get_blockdevice(one_slave,
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self.sysblock_dir, self.devnode_dir).devnodes:
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CACHE.set(cache_link, True)
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return True
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CACHE.set(cache_link, False)
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return False
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def is_md_raid(self):
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"""check if the device is the base of a md raid device
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"""
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## check the cache first
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cache_link = ["blockdevice_info", self.name, "is_md_raid"]
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cached = CACHE.get(cache_link)
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if not cached is None:
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return cached
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if self.range > 1:
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result = False
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elif self.size < MINIMUM_STORAGE_SIZE:
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result = False
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else:
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for hold in self.holders:
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if get_blockdevice(hold, self.sysblock_dir,
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self.devnode_dir).devnum[0] == MAJOR_DEVNUM_MD_RAID:
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result = True
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break
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else:
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result = False
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## store result and return
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CACHE.set(cache_link, result)
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return result
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def is_luks(self):
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"""check if the device is a luks container
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"""
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## check the cache first
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cache_link = ["blockdevice_info", self.name, "is_luks"]
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cached = CACHE.get(cache_link)
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if not cached is None:
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return cached
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if self.range > 1:
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result = False
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elif self.size < MINIMUM_STORAGE_SIZE:
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result = False
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elif self.is_lvm_pv():
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result = False
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elif self.is_md_raid():
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result = False
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else:
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## is the device a luks volume?
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prefs = _load_preferences()
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proc = subprocess.Popen(
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shell = False,
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stdout = subprocess.PIPE,
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stderr = subprocess.PIPE,
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args = [ prefs["Programs"]["cryptsetup"],
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"--batch-mode", "isLuks", self.devnodes[0]])
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proc.wait()
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result = proc.returncode == 0
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## store result and return
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CACHE.set(cache_link, result)
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return result
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def is_removable(self):
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"""check if the device is marked as 'removable'
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"""
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## check the cache first
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cache_link = ["blockdevice_info", self.name, "is_removable"]
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cached = CACHE.get(cache_link)
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if not cached is None:
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return cached
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removable_file = os.path.join(self.devdir, "removable")
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if os.path.isfile(removable_file):
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try:
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content = file(removable_file).read().strip()
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if content == "1":
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return True
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else:
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return False
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except IOError:
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result = False
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else:
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result = False
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CACHE.set(cache_link, result)
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return result
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def __get_dev_related(self, subdir):
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"""return the content of sub directories (e.g. 'holders' or 'slaves')
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"""
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try:
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return os.listdir(os.path.join(self.devdir, subdir))
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except OSError:
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return []
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def __get_size_human(self):
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"""return a human readable string representing the size of the device
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"""
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size = self.size
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if self.size > 5120:
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return "%dGB" % int(self.size/1024)
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else:
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return "%dMB" % self.size
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def __get_size(self):
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"""return the size (in MB) of the blockdevice
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"""
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default = 0
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try:
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size_kb = int(file(os.path.join(self.devdir, 'size')).read())
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return int(size_kb/1024)
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except OSError:
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return default
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except ValueError:
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return default
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def __get_major_minor(self):
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"""return the major and minor of the device"""
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default = (0, 0)
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try:
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content = file(os.path.join(self.devdir, "dev")).read()
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except IOError:
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return default
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try:
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major, minor = content.split(":", 1)
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except TypeError:
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return default
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try:
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return int(major), int(minor)
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except ValueError:
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return default
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def __get_device_range(self):
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"""number of possible subdevices
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partitionable blockdevices have a range > 1
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"""
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default = 1
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try:
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content = file(os.path.join(self.devdir, "range")).read()
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except IOError:
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return default
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try:
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return int(content)
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except ValueError:
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return default
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def __get_children(self):
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"""return all devices depending on the current one
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all holders, subdevices and children of subdevices
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"""
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direct_children = [
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get_blockdevice(child, self.sysblock_dir, self.devnode_dir).name
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for child in find_blockdevices(self.devdir)]
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direct_children.extend(self.holders[:])
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children = direct_children[:]
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for dchild in direct_children:
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children.extend(get_blockdevice(dchild, self.sysblock_dir,
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self.devnode_dir).children)
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return children
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def __get_device_nodes(self):
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"""get all device nodes with the major/minor combination of the device
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"""
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result = []
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major, minor = self.devnum
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def find_major_minor(arg, dirname, fnames):
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for fname in fnames:
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try:
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stat = os.stat(os.path.join(dirname, fname))
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## check if it is a blockdevice and compare major/minor
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if (stat.st_mode & 060000 == 060000) \
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and (os.major(stat.st_rdev) == major) \
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and (os.minor(stat.st_rdev) == minor):
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result.append(os.path.join(dirname, fname))
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except OSError:
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pass
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os.path.walk(self.devnode_dir, find_major_minor, None)
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return result
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def __get_uuid(self):
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"""determine the unique identifier of this device
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returns None in case of error or for invalid devices (see "is_valid")
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"""
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if not self.is_valid():
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return None
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## partitionable devices do not have a UUID
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if self.is_partitionable():
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return None
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## UUIDs of physical LVM volumes can only be determined via pvdisplay
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if self.is_lvm_pv():
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return self.__get_uuid_lvm_pv()
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## UUIDs of luks devices can be determined via luksDump
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if self.is_luks():
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return self.__get_uuid_luks()
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return self.__get_uuid_default()
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def __get_uuid_luks(self):
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"""determine the unique identifier of luks devices
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"""
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prefs = _load_preferences()
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try:
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proc = subprocess.Popen(
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shell = False,
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stdout = subprocess.PIPE,
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stderr = subprocess.PIPE,
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args = [ prefs["Programs"]["cryptsetup"],
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"luksUUID", self.devnodes[0] ])
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(output, error) = proc.communicate()
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except OSError, err_msg:
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LOGGER.warning("Failed to call '%s' to determine UUID: %s" \
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% (prefs["Programs"]["cryptsetup"], err_msg))
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return None
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if proc.returncode != 0:
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LOGGER.warning("Execution of '%s' for '%s' failed: %s" % \
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(prefs["Programs"]["cryptsetup"], self.devnodes[0],
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error))
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return None
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result = output.strip()
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if result:
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return result
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else:
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return None
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def __get_uuid_lvm_pv(self):
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"""determine the unique identifier of physical LVM volumes
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"""
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if not OPTIONAL_PROGS["lvm"]:
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## pvdisplay is not installed - skip it
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return None
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prefs = _load_preferences()
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try:
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proc = subprocess.Popen(
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shell = False,
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stdout = subprocess.PIPE,
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stderr = subprocess.PIPE,
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args = [ prefs["Programs"]["super"],
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prefs["Programs"]["CryptoBoxRootActions"],
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"program", "pvdisplay" ])
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(output, error) = proc.communicate()
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except OSError, err_msg:
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LOGGER.warning("Failed to call '%s' via 'super' to determine " \
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% prefs["Programs"]["pvdisplay"] + "UUID: %s" % err_msg)
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return None
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if proc.returncode == 101:
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## pvdisplay is not installed
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OPTIONAL_PROGS["lvm"] = False
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LOGGER.warning("'lvm' is not installed - I will not try it again")
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return None
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if proc.returncode != 0:
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LOGGER.warning("Execution of 'pvdisplay' failed: %s" % error)
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return None
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for line in output.splitlines():
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items = line.strip().split(":")
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if (len(items) == 12) and (items[0] in self.devnodes):
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return items[11]
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## not found
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return None
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def __get_uuid_default(self):
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"""determine the unique identifier for non-special devices
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|
|
luks and lvm_pv devices must be treated differently
|
|
"""
|
|
prefs = _load_preferences()
|
|
try:
|
|
proc = subprocess.Popen(
|
|
shell = False,
|
|
stdout = subprocess.PIPE,
|
|
stderr = subprocess.PIPE,
|
|
args = [ prefs["Programs"]["blkid"],
|
|
"-s", "UUID",
|
|
"-o", "value",
|
|
"-c", os.devnull,
|
|
"-w", os.devnull,
|
|
self.devnodes[0] ])
|
|
(output, error) = proc.communicate()
|
|
except OSError, err_msg:
|
|
LOGGER.warning("Failed to call '%s' to determine UUID: %s" % \
|
|
(prefs["Programs"]["blkid"], err_msg))
|
|
return None
|
|
if proc.returncode != 0:
|
|
LOGGER.warning("Execution of '%s' for '%s' failed: %s" % \
|
|
(prefs["Programs"]["blkid"], self.devnodes[0],
|
|
error.strip()))
|
|
return None
|
|
result = output.strip()
|
|
if result:
|
|
return result
|
|
else:
|
|
return None
|
|
|
|
|
|
def __get_label(self):
|
|
"""determine the label of a filesystem contained in a device
|
|
|
|
return None for errors, empty labels and for luks or non-storage devices
|
|
"""
|
|
if not self.is_valid():
|
|
return None
|
|
if self.is_luks():
|
|
return None
|
|
prefs = _load_preferences()
|
|
try:
|
|
proc = subprocess.Popen(
|
|
shell = False,
|
|
stdout = subprocess.PIPE,
|
|
stderr = subprocess.PIPE,
|
|
args = [ prefs["Programs"]["blkid"],
|
|
"-s", "LABEL",
|
|
"-o", "value",
|
|
"-c", os.devnull,
|
|
"-w", os.devnull,
|
|
self.devnodes[0]])
|
|
(output, error) = proc.communicate()
|
|
except OSError, err_msg:
|
|
LOGGER.warning("Failed to call '%s' to determine label for " \
|
|
% prefs["Programs"]["blkid"] + "'%s': %s" % \
|
|
(self.devnodes[0], err_msg))
|
|
return None
|
|
if proc.returncode != 0:
|
|
LOGGER.warning("Execution of '%s' for '%s' failed: %s" % \
|
|
(prefs["Programs"]["blkid"], self.devnodes[0],
|
|
error.strip()))
|
|
return None
|
|
result = output.strip()
|
|
if result:
|
|
return result
|
|
else:
|
|
return None
|
|
|
|
|
|
def __get_type_id(self):
|
|
"""determine the type id of a filesystem contained in a device
|
|
|
|
possible results are: ext2, ext3, vfat, reiserfs, swap, ...
|
|
return None for errors, empty labels and for luks or non-storage devices
|
|
"""
|
|
if not self.is_valid():
|
|
return None
|
|
if self.is_luks():
|
|
return None
|
|
prefs = _load_preferences()
|
|
try:
|
|
proc = subprocess.Popen(
|
|
shell = False,
|
|
stdout = subprocess.PIPE,
|
|
stderr = subprocess.PIPE,
|
|
args = [ prefs["Programs"]["blkid"],
|
|
"-s", "TYPE",
|
|
"-o", "value",
|
|
"-c", os.devnull,
|
|
"-w", os.devnull,
|
|
self.devnodes[0]])
|
|
(output, error) = proc.communicate()
|
|
except OSError, err_msg:
|
|
LOGGER.warning("Failed to call '%s' to determine type id for" \
|
|
% prefs["Programs"]["blkid"] + " '%s': %s" % \
|
|
(self.devnodes[0], err_msg))
|
|
return None
|
|
if proc.returncode != 0:
|
|
LOGGER.warning("Execution of '%s' for '%s' failed: %s" % \
|
|
(prefs["Programs"]["blkid"], self.devnodes[0],
|
|
error.strip()))
|
|
return None
|
|
result = output.strip()
|
|
if result:
|
|
return result
|
|
else:
|
|
return None
|
|
|
|
|
|
def __eq__(self, device):
|
|
"""compare two blockdevice objects
|
|
"""
|
|
return self.name == device.name
|
|
|
|
|
|
def __str__(self):
|
|
"""display the name of the device
|
|
"""
|
|
return self.name
|
|
|
|
|
|
def info(self):
|
|
"""display some information about the device
|
|
"""
|
|
output = "%s:\n" % self.name
|
|
output += "\t%s:\t%s\n" % ("blockdir", self.devdir)
|
|
output += "\t%s:\t%s\n" % ("major/minor", self.devnum)
|
|
output += "\t%s:\t\t%s\n" % ("label", self.label)
|
|
output += "\t%s:\t\t%s\n" % ("UUID", self.uuid)
|
|
output += "\t%s:\t\t%s\n" % ("range", self.range)
|
|
output += "\t%s:\t\t%s\n" % ("size", self.size)
|
|
output += "\t%s:\t\t%s\n" % ("slaves", self.slaves)
|
|
output += "\t%s:\t%s\n" % ("holders", self.holders)
|
|
output += "\t%s:\t%s\n" % ("children", self.children)
|
|
output += "\t%s:\t%s\n" % ("device nodes", self.devnodes)
|
|
output += "\tflags:\t\t"
|
|
for funcname in [ func for func in dir(self)
|
|
if func.startswith("is_") and callable(getattr(self, func))]:
|
|
if getattr(self, funcname)():
|
|
output += "%s " % funcname[3:]
|
|
output += "\n"
|
|
return output
|
|
|
|
|
|
class BlockdeviceCache:
|
|
"""manage cached results of blockdevce queries
|
|
|
|
the cache expires every 60 seconds or as soon as CACHE_MONITOR_FILE changes
|
|
"""
|
|
|
|
def __init__(self):
|
|
self.values = {}
|
|
self.expires = None
|
|
self.partitions_save = None
|
|
self.reset()
|
|
|
|
|
|
def reset(self, link=None):
|
|
"""empty the cache and reset the expire time
|
|
"""
|
|
if not link:
|
|
self.values = {}
|
|
try:
|
|
self.partitions_save = file(CACHE_MONITOR_FILE).read()
|
|
except IOError, err_msg:
|
|
LOGGER.warning("Failed to read '%s': %s" % \
|
|
(CACHE_MONITOR_FILE, err_msg))
|
|
self.partitions_save = ""
|
|
self.expires = int(time.time()) + CACHE_EXPIRE_SECONDS
|
|
else:
|
|
## we do no reset the expire date
|
|
self.set(link, {})
|
|
|
|
|
|
def __is_expired(self):
|
|
"""check if the cache is expired
|
|
"""
|
|
try:
|
|
if (file(CACHE_MONITOR_FILE).read() != self.partitions_save) or \
|
|
(self.expires < int(time.time())):
|
|
return True
|
|
except IOError:
|
|
LOGGER.warning("Failed to read '%s': %s" % \
|
|
(CACHE_MONITOR_FILE, err_msg))
|
|
return False
|
|
|
|
|
|
def get(self, link):
|
|
"""return a cached value
|
|
|
|
"link" is an array of the hierachie of the accessed item
|
|
e.g. link = ["blockdevices", "hda"]
|
|
return None if the value is not in the cache or if CACHE_ENABLED is False
|
|
"""
|
|
if not CACHE_ENABLED:
|
|
return None
|
|
if self.__is_expired():
|
|
self.reset()
|
|
## walk down the tree
|
|
ref = self.values
|
|
for element in link:
|
|
if element in ref:
|
|
ref = ref[element]
|
|
else:
|
|
return None
|
|
return ref
|
|
|
|
|
|
def set(self, link, item):
|
|
"""store an item in the cache
|
|
|
|
"link" is an array of the hierachie of the accessed item
|
|
e.g. link = ["blockdevices", "hda"]
|
|
"""
|
|
if not CACHE_ENABLED:
|
|
return
|
|
## walk down the tree
|
|
ref = self.values
|
|
for element in link[:-1]:
|
|
if not element in ref:
|
|
## create a non-existing sub element
|
|
ref[element] = {}
|
|
ref = ref[element]
|
|
## store the item
|
|
ref[link[-1]] = item
|
|
|
|
|
|
|
|
def get_blockdevice(dev,
|
|
sysblock_dir=DEFAULT_SYSBLOCK_DIR,
|
|
devnode_dir=DEFAULT_DEVNODE_DIR):
|
|
if os.path.isabs(dev):
|
|
## it is an absolute path
|
|
if dev.startswith(devnode_dir):
|
|
## it is the name of a devicenode (e.g.: '/dev/hda1')
|
|
## simplify the path first
|
|
dev = os.path.realpath(dev)
|
|
found_dev = [ a_dev for a_dev in Blockdevices(
|
|
sysblock_dir, devnode_dir).get_devices()
|
|
if dev in a_dev.devnodes ]
|
|
if found_dev:
|
|
devdir = found_dev[0].devdir
|
|
else:
|
|
return None
|
|
else:
|
|
## it is the path of a /sys/ subdirectory (e.g.: '/sys/block/hda')
|
|
if os.path.isfile(os.path.join(dev, "dev")):
|
|
devdir = dev
|
|
else:
|
|
return None
|
|
else:
|
|
## the name of a blockdevice (e.g.: 'dm-0')
|
|
for one_devdir in find_blockdevices(sysblock_dir):
|
|
if os.path.basename(one_devdir) == dev:
|
|
devdir = one_devdir
|
|
break
|
|
else:
|
|
return None
|
|
devname = os.path.basename(devdir)
|
|
cache_link = ["blockdevices", devname]
|
|
dev = CACHE.get(cache_link)
|
|
if dev is None:
|
|
dev = Blockdevice(devdir, sysblock_dir, devnode_dir)
|
|
CACHE.set(cache_link, dev)
|
|
return dev
|
|
|
|
|
|
def find_blockdevices(top_dir):
|
|
|
|
cache_link = ["blockdevice_dirs", top_dir]
|
|
cached = CACHE.get(cache_link)
|
|
if not cached is None:
|
|
return cached[:]
|
|
|
|
dev_dirs = []
|
|
|
|
def look4dev_dirs(arg, dirname, fnames):
|
|
## ignore the top level directory to avoid infinite recursion for
|
|
## get_children
|
|
if os.path.samefile(dirname, top_dir):
|
|
return
|
|
## add directories containing the file 'dev' to the list
|
|
if (arg in fnames) and os.path.isfile(os.path.join(dirname, arg)):
|
|
dev_dirs.append(dirname)
|
|
for fname in fnames:
|
|
## remove symlinks and non-directories
|
|
fullname = os.path.join(dirname, fname)
|
|
if os.path.islink(fullname) or (not os.path.isdir(fullname)):
|
|
fnames.remove(fname)
|
|
|
|
os.path.walk(top_dir, look4dev_dirs, 'dev')
|
|
CACHE.set(cache_link, dev_dirs)
|
|
return dev_dirs[:]
|
|
|
|
|
|
def find_lvm_pv():
|
|
"""return the blockdevice names of all physical LVM volumes
|
|
"""
|
|
if not OPTIONAL_PROGS["lvm"]:
|
|
return []
|
|
cache_link = ["lvm", "pv"]
|
|
cached = CACHE.get(cache_link)
|
|
if not cached is None:
|
|
return cached[:]
|
|
|
|
prefs = _load_preferences()
|
|
result = None
|
|
try:
|
|
proc = subprocess.Popen(
|
|
shell = False,
|
|
stdout = subprocess.PIPE,
|
|
stderr = subprocess.PIPE,
|
|
args = [ prefs["Programs"]["super"],
|
|
prefs["Programs"]["CryptoBoxRootActions"],
|
|
"program", "pvdisplay" ])
|
|
(output, error) = proc.communicate()
|
|
except OSError, err_msg:
|
|
LOGGER.info("Failed to call 'pvdisplay' via 'super': %s" % err_msg)
|
|
result = []
|
|
if proc.returncode == 101:
|
|
## pvdisplay is not installed
|
|
OPTIONAL_PROGS["lvm"] = False
|
|
LOGGER.warning("'lvm' is not installed - I will not try it again")
|
|
return []
|
|
if proc.returncode != 0:
|
|
LOGGER.info("Execution of 'pvdisplay' failed: %s" % error.strip())
|
|
result = []
|
|
if result is None:
|
|
result = []
|
|
for line in output.splitlines():
|
|
result.append(line.split(":", 1)[0].strip())
|
|
CACHE.set(cache_link, result)
|
|
return result[:]
|
|
|
|
|
|
def get_sorted_devices(names):
|
|
"""return the names of devices in a sorted order
|
|
|
|
e.g.: "hda1", "hda5", "hda6", ..., "hda10", "hda11"
|
|
"""
|
|
# TODO: implement this for devicenames like "hda12"
|
|
def compare_device_names(x, y):
|
|
if x.name < y.name:
|
|
return -1
|
|
elif x.name == y.name:
|
|
return 0
|
|
else:
|
|
return 1
|
|
|
|
result = names[:]
|
|
result.sort(cmp=compare_device_names)
|
|
return result
|
|
|
|
|
|
def _load_preferences():
|
|
prefs = cryptobox.core.settings.get_current_settings()
|
|
if not prefs is None:
|
|
## now the preferences are loaded
|
|
return prefs
|
|
## we have to load an emergency fallback for proper function
|
|
## this is mainly useful for local testing
|
|
root_dir = os.path.realpath(os.path.join(globals()["cryptobox"].__path__[0],
|
|
os.path.pardir, os.path.pardir))
|
|
config_file = os.path.join(root_dir, "bin", "cryptobox.conf")
|
|
## we have to chdir to the 'bin' directory - otherwise the paths in
|
|
## cryptobox.conf do not work
|
|
os.chdir(os.path.dirname(config_file))
|
|
return cryptobox.core.settings.CryptoBoxSettings(config_file)
|
|
|
|
|
|
|
|
## initialize cache
|
|
CACHE = BlockdeviceCache()
|
|
|
|
|
|
if __name__ == '__main__':
|
|
## list the properties of all available devices
|
|
## this is just for testing purposes
|
|
blocks = Blockdevices().get_devices()
|
|
|
|
## do we want to show the result?
|
|
def show(text=""):
|
|
if IS_VISIBLE:
|
|
print text
|
|
|
|
if len(blocks) > 0:
|
|
## show all devices and their properties
|
|
show("Properties of all devices:")
|
|
for device in blocks:
|
|
show(device.info())
|
|
|
|
## discover all self-check methods
|
|
example = blocks[0]
|
|
flag_checker = [ method for method in dir(example)
|
|
if callable(getattr(example, method))
|
|
and method.startswith("is_")]
|
|
## list all checks and the respective devices
|
|
for check in flag_checker:
|
|
show("List of '%s' devices:" % check[3:])
|
|
for device in blocks:
|
|
if getattr(device, check)():
|
|
show("\t%s" % device)
|
|
show()
|
|
|