moved pythonrewrite branch to trunk

bin/cryptobox.pl → bin-perl-old/cryptobox.pl

@@ -532,7 +532,7 @@ if ( ! &check_ssl()) {
 		if ($device eq '') {
 			&debug_msg(DEBUG_INFO, "invalid device: " . $query->param('device'));
 			$pagedata->setValue('Data.Warning', 'InvalidDevice');
-			$pagedata->setValue('Data.Action', 'empty');
+			$pagedata->setValue('Data.Action', 'emptu');
 		} elsif ( ! &check_config()) {
 			$pagedata->setValue('Data.Warning', 'NotInitialized');
 			$pagedata->setValue('Data.Action', 'form_init');

bin/CryptoBox.py

@@ -0,0 +1,276 @@
+#!/usr/bin/env python2.4
+'''
+This is the web interface for a fileserver managing encrypted filesystems.
+ 
+It was originally written in bash/perl. Now a complete rewrite is in
+progress. So things might be confusing here. Hopefully not for long.
+:)
+'''
+
+# check python version
+import sys
+(ver_major, ver_minor, ver_sub, ver_desc, ver_subsub) = sys.version_info
+if (ver_major < 2) or ((ver_major == 2) and (ver_minor < 4)):
+	sys.stderr.write("You need a python version >= 2.4\nCurrent version is:\n %s\n" % sys.version)
+	sys.exit(1)
+
+import CryptoBoxContainer
+from CryptoBoxExceptions import *
+import re
+import os
+import CryptoBoxTools
+import subprocess
+
+
+
+class CryptoBox:
+	'''this class rules them all!
+
+	put things like logging, conf and oter stuff in here,
+	that might be used by more classes, it will be passed on to them'''
+
+	VERSION = "0.3~1"
+
+	def __init__(self, config_file=None):
+		import CryptoBoxSettings
+		self.log = self.__getStartupLogger()
+		self.prefs = CryptoBoxSettings.CryptoBoxSettings(config_file)
+		self.__runTests()
+
+
+	def __getStartupLogger(self):	
+		import logging
+		'''initialises the logging system
+		
+		use it with: 'self.log.[debug|info|warning|error|critical](logmessage)'
+		all classes should get the logging instance during __init__:
+			self.log = logging.getLogger("CryptoBox")
+
+		first we output all warnings/errors to stderr
+		as soon as we opened the config file successfully, we redirect debug output
+		to the configured destination'''
+		## basicConfig(...) needs python >= 2.4
+		try:
+			log_handler = logging.getLogger("CryptoBox")
+			logging.basicConfig(
+				format='%(asctime)s CryptoBox %(levelname)s: %(message)s',
+				stderr=sys.stderr)
+			log_handler.setLevel(logging.ERROR)
+			log_handler.info("loggingsystem is up'n running")
+			## from now on everything can be logged via self.log...
+		except:
+			raise CBEnvironmentError("couldn't initialise the loggingsystem. I give up.")
+		return log_handler
+
+
+	# do some initial checks
+	def __runTests(self):
+		self.__runTestUID()
+		self.__runTestRootPriv()
+
+	
+	def __runTestUID(self):
+		if os.geteuid() == 0:
+			raise CBEnvironmentError("you may not run the cryptobox as root")
+
+
+	def __runTestRootPriv(self):
+		"""try to run 'super' with 'CryptoBoxRootActions'"""
+		try:
+			devnull = open(os.devnull, "w")
+		except IOError:
+			raise CBEnvironmentError("could not open %s for writing!" % os.devnull)
+		try:
+			prog_super = self.prefs["Programs"]["super"]
+		except KeyError:
+			raise CBConfigUndefinedError("Programs", "super")
+		try:
+			prog_rootactions = self.prefs["Programs"]["CryptoBoxRootActions"]
+		except KeyError:
+			raise CBConfigUndefinedError("Programs", "CryptoBoxRootActions")
+		try:
+			proc = subprocess.Popen(
+				shell = False,
+				stdout = devnull,
+				stderr = devnull,
+				args = [prog_super, prog_rootactions, "check"])
+		except OSError:
+			raise CBEnvironmentError("failed to execute 'super' (%s)" % self.prefs["Programs"]["super"])
+		proc.wait()
+		if proc.returncode != 0:
+			raise CBEnvironmentError("failed to call CryptoBoxRootActions (%s) via 'super' - maybe you did not add the appropriate line to /etc/super.tab?" % prog_rootactions)
+
+
+	# this method just demonstrates inheritance effects - may be removed
+	def cbx_inheritance_test(self, string="you lucky widow"):
+		self.log.info(string)
+	
+
+# RFC: why should CryptoBoxProps inherit CryptoBox? [l]
+# RFC: shouldn't we move all useful functions of CryptoBoxProps to CryptoBox? [l]
+class CryptoBoxProps(CryptoBox):
+	'''Get and set the properties of a CryptoBox
+
+	This class contains all available devices that may be accessed.
+	All properties of the cryptobox can be accessed by this class.
+	'''
+
+	def __init__(self, config_file=None):
+		'''read config and fill class variables'''
+		CryptoBox.__init__(self, config_file)
+		self.reReadContainerList()
+	
+
+	def reReadContainerList(self):
+		self.log.debug("rereading container list")
+		self.containers = []
+		for device in CryptoBoxTools.getAvailablePartitions():
+			if self.isDeviceAllowed(device) and not self.isConfigPartition(device):
+				self.containers.append(CryptoBoxContainer.CryptoBoxContainer(device, self))
+		## sort by container name
+		self.containers.sort(cmp = lambda x,y: x.getName() < y.getName() and -1 or 1)
+	
+
+	def isConfigPartition(self, device):
+		proc = subprocess.Popen(
+			shell = False,
+			stdout = subprocess.PIPE,
+			args = [
+				self.prefs["Programs"]["blkid"],
+				"-c", os.path.devnull,
+				"-o", "value",
+				"-s", "LABEL",
+				device])
+		(output, error) = proc.communicate()
+		return output.strip() == self.prefs["Main"]["ConfigVolumeLabel"]
+
+
+	def isDeviceAllowed(self, devicename):
+		"check if a device is white-listed for being used as cryptobox containers"
+		import types
+		allowed = self.prefs["Main"]["AllowedDevices"]
+		if type(allowed) == types.StringType: allowed = [allowed]
+		for a_dev in allowed:
+			"remove double dots and so on ..."
+			real_device = os.path.realpath(devicename)
+			if a_dev and re.search('^' + a_dev, real_device):	return True
+		return False
+
+
+	def getLogData(self, lines=None, maxSize=None):
+		"""get the most recent log entries of the cryptobox
+
+		the maximum number and size of these entries can be limited by 'lines' and 'maxSize'
+		"""
+		# return nothing if the currently selected log output is not a file
+		try:
+			if self.prefs["Log"]["Destination"].upper() != "FILE": return []
+			log_file = self.prefs["Log"]["Details"]
+		except KeyError:
+			self.log.error("could not evaluate one of the following config settings: [Log]->Destination or [Log]->Details")
+			return []
+		try:
+			fd = open(log_file, "r")
+			if maxSize:	fd.seek(-maxSize, 2)	# seek relative to the end of the file
+			content = fd.readlines()
+			fd.close()
+		except IOError:
+			self.log.warn("failed to read the log file (%s)" % log_file)
+			return []
+		if lines:	content = content[-lines:]
+		content.reverse()
+		return content
+
+
+	def getContainerList(self, filterType=None, filterName=None):
+		"retrieve the list of all containers of this cryptobox"
+		try:
+			result = self.containers[:]
+			if filterType != None:
+				if filterType in range(len(CryptoBoxContainer.Types)):
+					return [e for e in self.containers if e.getType() == filterType]
+				else:
+					self.log.info("invalid filterType (%d)" % filterType)
+					result.clear()
+			if filterName != None:
+				result = [e for e in self.containers if e.getName() == filterName]
+			return result
+		except AttributeError:
+			return []
+
+
+	def getContainer(self, device):
+		"retrieve the container element for this device"
+		all = [e for e in self.getContainerList() if e.device == device]
+		if all:
+			return all[0]
+		else:
+			return None
+
+
+	def setNameForUUID(self, uuid, name):
+		"assign a name to a uuid in the ContainerNameDatabase"
+		used_uuid = self.getUUIDForName(name)
+		"first remove potential conflicting uuid/name combination"
+		if used_uuid:
+			## remember the container which name was overriden
+			for e in self.containers:
+				if e.getName() == name:
+					forcedRename = e
+					break
+			del self.prefs.nameDB[used_uuid]
+		self.prefs.nameDB[uuid] = name
+		self.prefs.nameDB.write()
+		## rename the container that lost its name (necessary while we use cherrypy)
+		if used_uuid:
+			## this is surely not the best way to regenerate the name
+			dev = e.getDevice()
+			old_index = self.containers.index(e)
+			self.containers.remove(e)
+			self.containers.insert(old_index, CryptoBoxContainer.CryptoBoxContainer(dev,self))
+		## there should be no reason for any failure
+		return True
+
+
+	def getNameForUUID(self, uuid):
+		"get the name belonging to a specified key (usually the UUID of a fs)"
+		try:
+			return self.prefs.nameDB[uuid]
+		except KeyError:
+			return None
+	
+
+	def getUUIDForName(self, name):
+		"""	get the key belonging to a value in the ContainerNameDatabase
+			this is the reverse action of 'getNameForUUID'	"""
+		for key in self.prefs.nameDB.keys():
+			if self.prefs.nameDB[key] == name: return key
+		"the uuid was not found"
+		return None
+	
+
+	def removeUUID(self, uuid):
+		if uuid in self.prefs.nameDB.keys():
+			del self.prefs.nameDB[uuid]
+			return True
+		else:
+			return False
+
+
+	def getAvailableLanguages(self):
+		'''reads all files in path LangDir and returns a list of
+		basenames from existing hdf files, that should are all available
+		languages'''
+		languages = [ f.rstrip(".hdf")
+			for f in os.listdir(self.prefs["Locations"]["LangDir"])
+			if f.endswith(".hdf") ]
+		if len(languages) < 1:
+			self.log.error("No .hdf files found! The website won't render properly.")
+		return languages
+
+
+
+
+if __name__ == "__main__":
+	cb = CryptoBoxProps()
+

bin/CryptoBoxContainer.py

@@ -0,0 +1,607 @@
+#!/usr/bin/env python2.4
+
+## check python version
+import sys
+(ver_major, ver_minor, ver_sub, ver_desc, ver_subsub) = sys.version_info
+if (ver_major < 2) or ((ver_major == 2) and (ver_minor < 4)):
+	sys.stderr.write("You need a python version >= 2.4\nCurrent version is:\n %s\n" % sys.version)
+	sys.exit(1)
+
+import subprocess
+import os
+import re
+import logging
+from CryptoBoxExceptions import *
+
+"""exceptions:
+	VolumeIsActive
+	NameActivelyUsed
+	InvalidName
+	InvalidPassword
+	InvalidType
+	CreateError
+	MountError
+	ChangePasswordError
+	"""
+
+class CryptoBoxContainer:
+
+	Types = {
+		"unused":0,
+		"plain":1,
+		"luks":2,
+		"swap":3}
+	
+
+	__fsTypes = {
+		"plain":["ext3", "ext2", "vfat", "reiser"],
+		"swap":["swap"]}
+	# TODO: more filesystem types? / check 'reiser'
+
+	__dmDir = "/dev/mapper"
+
+
+	def __init__(self, device, cbox):
+		self.device = device
+		self.cbox = cbox
+		self.log = logging.getLogger("CryptoBox")
+		self.resetObject()
+
+
+	def getName(self):
+		return self.name
+
+
+	def setName(self, new_name):
+		if new_name == self.name: return
+		if self.isMounted():
+			raise CBVolumeIsActive("the container must be inactive during renaming")
+		if not re.search(r'^[a-zA-Z0-9_\.\- ]+$', new_name):
+			raise CBInvalidName("the supplied new name contains illegal characters")
+		"check for active partitions with the same name"
+		prev_name_owner = self.cbox.getContainerList(filterName=new_name)
+		if prev_name_owner:
+			for a in prev_name_owner:
+				if a.isMounted():
+					raise CBNameActivelyUsed("the supplied new name is already in use for an active partition")
+		if not self.cbox.setNameForUUID(self.uuid, new_name):
+			raise CBContainerError("failed to change the volume name for unknown reasons")
+		self.name = new_name
+
+
+	def getDevice(self):
+		return self.device
+
+
+	def getType(self):
+		return self.type
+
+
+	def isMounted(self):
+		return os.path.ismount(self.__getMountPoint())
+	
+
+	def getCapacity(self):
+		"""return the current capacity state of the volume
+
+		the volume may not be mounted
+		the result is a tuple of values in megabyte:
+			(size, available, used)
+		"""
+		info = os.statvfs(self.__getMountPoint())
+		return (
+			int(info.f_bsize*info.f_blocks/1024/1024),
+			int(info.f_bsize*info.f_bavail/1024/1024),
+			int(info.f_bsize*(info.f_blocks-info.f_bavail)/1024/1024))
+	
+
+	def getSize(self):
+		"""return the size of the block device (_not_ of the filesystem)
+
+		the result is a value in megabyte
+		an error is indicated by "-1"
+		"""
+		import CryptoBoxTools
+		return CryptoBoxTools.getBlockDeviceSize(self.device)
+
+
+	def resetObject(self):
+		"""	recheck the information about this container
+			this is especially useful after changing the type via 'create'	"""
+		self.uuid = self.__getUUID()
+		self.type = self.__getTypeOfPartition()
+		self.name = self.__getNameOfContainer()
+		if self.type == self.Types["luks"]:
+			self.mount = self.__mountLuks
+			self.umount = self.__umountLuks
+		elif self.type == self.Types["plain"]:
+			self.mount = self.__mountPlain
+			self.umount = self.__umountPlain
+
+
+	def create(self, type, password=None):
+		old_name = self.getName()
+		if type == self.Types["luks"]:
+			self.__createLuks(password)
+		elif type == self.Types["plain"]:
+			self.__createPlain()
+		else:
+			raise CBInvalidType("invalid container type (%d) supplied" % (type, ))
+		## no exception was raised during creation -> we can continue
+		## reset the properties (encryption state, ...) of the device
+		self.resetObject()
+		## restore the old name (must be after resetObject)
+		self.setName(old_name)
+
+
+	def changePassword(self, oldpw, newpw):
+		if self.type != self.Types["luks"]:
+			raise CBInvalidType("changing of password is possible only for luks containers")
+		if not oldpw:
+			raise CBInvalidPassword("no old password supplied for password change")
+		if not newpw:
+			raise CBInvalidPassword("no new password supplied for password change")
+		"return if new and old passwords are the same"
+		if oldpw == newpw: return
+		if self.isMounted():
+			raise CBVolumeIsActive("this container is currently active")
+		devnull = None
+		try:
+			devnull = open(os.devnull, "w")
+		except IOError:
+			self.log.warn("Could not open %s" % (os.devnull, ))
+		"remove any potential open luks mapping"
+		self.__umountLuks()
+		"create the luks header"
+		proc = subprocess.Popen(
+			shell = False,
+			stdin = subprocess.PIPE,
+			stdout = subprocess.PIPE,
+			stderr = subprocess.PIPE,
+			args = [
+				self.cbox.prefs["Programs"]["super"],
+				self.cbox.prefs["Programs"]["CryptoBoxRootActions"],
+				"cryptsetup",
+				"luksAddKey",
+				self.device,
+				"--batch-mode"])
+		proc.stdin.write("%s\n%s" % (oldpw, newpw))
+		(output, errout) = proc.communicate()
+		if proc.returncode != 0:
+			errorMsg = "Could not add a new luks key: %s - %s" % (output.strip(), errout.strip(), )
+			self.log.error(errorMsg)
+			raise CBChangePasswordError(errorMsg)
+		## retrieve the key slot we used for unlocking
+		keys_found = re.search(r'key slot (\d{1,3}) unlocked', output).groups()
+		if keys_found:
+			keyslot = int(keys_found[0])
+		else:
+			raise CBChangePasswordError("could not get the old key slot")
+		"remove the old key"
+		proc = subprocess.Popen(
+			shell = False,
+			stdin = None,
+			stdout = devnull,
+			stderr = subprocess.PIPE,
+			args = [
+				self.cbox.prefs["Programs"]["cryptsetup"],
+				"--batch-mode",
+				"luksDelKey",
+				self.device,
+				"%d" % (keyslot, )])
+		proc.wait()
+		if proc.returncode != 0:
+			errorMsg = "Could not remove the old luks key: %s" % (proc.stderr.read().strip(), )
+			self.log.error(errorMsg)
+			raise CBChangePasswordError(errorMsg)
+		
+
+
+	" ****************** internal stuff ********************* "
+
+	def __getNameOfContainer(self):
+		"retrieve the name of the container by querying the database"
+		def_name = self.cbox.getNameForUUID(self.uuid)
+		if def_name: return def_name
+		"there is no name defined for this uuid - we will propose a good one"
+		prefix = self.cbox.prefs["Main"]["DefaultVolumePrefix"]
+		unused_found = False
+		counter = 1
+		while not unused_found:
+			guess = prefix + str(counter)
+			if self.cbox.getUUIDForName(guess):
+				counter += 1
+			else:
+				unused_found = True
+		self.cbox.setNameForUUID(self.uuid, guess)
+		return guess
+
+
+	def __getUUID(self):
+		if self.__getTypeOfPartition() == self.Types["luks"]:
+			guess = self.__getLuksUUID()
+		else:
+			guess = self.__getNonLuksUUID()
+		## did we get a valid value?
+		if guess:
+			return guess
+		else:
+			## emergency default value
+			return self.device.replace(os.path.sep, "_")
+
+
+	def __getLuksUUID(self):
+		"""get uuid for luks devices"""
+		proc = subprocess.Popen(
+			shell = False,
+			stdout = subprocess.PIPE,
+			stderr = subprocess.PIPE,
+			args = [self.cbox.prefs["Programs"]["cryptsetup"],
+				"luksUUID",
+				self.device])
+		(stdout, stderr) = proc.communicate()
+		if proc.returncode != 0:
+			self.cbox.log.info("could not retrieve luks uuid (%s): %s", (self.device, stderr.strip()))
+			return None
+		return stdout.strip()
+
+	
+	def __getNonLuksUUID(self):
+		"""return UUID for ext2/3 and vfat filesystems"""
+		try:
+			devnull = open(os.devnull, "w")
+		except IOError:
+			self.warn("Could not open %s" % (os.devnull, ))
+		proc = subprocess.Popen(
+			shell=False,
+			stdout=subprocess.PIPE,
+			stderr=subprocess.PIPE,
+			args=[self.cbox.prefs["Programs"]["blkid"],
+				"-s", "UUID",
+				"-o", "value",
+				"-c", os.devnull,
+				"-w", os.devnull,
+				self.device])
+		(stdout, stderr) = proc.communicate()
+		devnull.close()
+		## execution failed?
+		if proc.returncode != 0:
+			self.log.info("retrieving of partition type (%s) via 'blkid' failed: %s - maybe it is encrypted?" % (self.device, stderr.strip()))
+			return None
+		## return output of blkid
+		return stdout.strip()
+
+
+	def __getTypeOfPartition(self):
+		"retrieve the type of the given partition (see CryptoBoxContainer.Types)"
+		if self.__isLuksPartition(): return self.Types["luks"]
+		typeOfPartition = self.__getTypeIdOfPartition()
+		if typeOfPartition in self.__fsTypes["plain"]:
+			return self.Types["plain"]
+		if typeOfPartition in self.__fsTypes["swap"]:
+			return self.Types["swap"]
+		return self.Types["unused"]
+
+
+	def __getTypeIdOfPartition(self):
+		"returns the type of the partition (see 'man blkid')"
+		devnull = None
+		try:
+			devnull = open(os.devnull, "w")
+		except IOError:
+			self.log.warn("Could not open %s" % (os.devnull, ))
+		proc = subprocess.Popen(
+			shell=False,
+			stdin=None,
+			stdout=subprocess.PIPE,
+			stderr=subprocess.PIPE,
+			args=[self.cbox.prefs["Programs"]["blkid"],
+				"-s", "TYPE",
+				"-o", "value",
+				"-c", os.devnull,
+				"-w", os.devnull,
+				self.device])
+		proc.wait()
+		output = proc.stdout.read().strip()
+		if proc.returncode != 0:
+			self.log.warn("retrieving of partition type via 'blkid' failed: %s" % (proc.stderr.read().strip(), ))
+			return None
+		devnull.close()
+		return output
+
+
+	def __isLuksPartition(self):
+		"check if the given device is a luks partition"
+		devnull = None
+		try:
+			devnull = open(os.devnull, "w")
+		except IOError:
+			self.log.warn("Could not open %s" % (os.devnull, ))
+		proc = subprocess.Popen(
+			shell = False,
+			stdin = None,
+			stdout = devnull,
+			stderr = devnull,
+			args = [
+				self.cbox.prefs["Programs"]["cryptsetup"],
+				"--batch-mode",
+				"isLuks",
+				self.device])
+		proc.wait()
+		devnull.close()
+		return proc.returncode == 0
+
+
+	def __getMountPoint(self):
+		"return the name of the mountpoint of this volume"
+		return os.path.join(self.cbox.prefs["Locations"]["MountParentDir"], self.name)
+
+
+	def __mountLuks(self, password):
+		"mount a luks partition"
+		if not password:
+			raise CBInvalidPassword("no password supplied for luksOpen")
+		if self.isMounted(): raise CBVolumeIsActive("this container is already active")
+		self.__umountLuks()
+		try:
+			devnull = open(os.devnull, "w")
+		except IOError:
+			self.log.warn("Could not open %s" % (os.devnull, ))
+		self.__cleanMountDirs()
+		if not os.path.exists(self.__getMountPoint()):
+			os.mkdir(self.__getMountPoint())
+		if not os.path.exists(self.__getMountPoint()):
+			errorMsg = "Could not create mountpoint (%s)" % (self.__getMountPoint(), )
+			self.log.error(errorMsg)
+			raise CBMountError(errorMsg)
+		proc = subprocess.Popen(
+			shell = False,
+			stdin = subprocess.PIPE,
+			stdout = devnull,
+			stderr = subprocess.PIPE,
+			args = [
+				self.cbox.prefs["Programs"]["super"],
+				self.cbox.prefs["Programs"]["CryptoBoxRootActions"],
+				"cryptsetup",
+				"luksOpen",
+				self.device,
+				self.name,
+				"--batch-mode"])
+		proc.stdin.write(password)
+		(output, errout) = proc.communicate()
+		if proc.returncode != 0:
+			errorMsg = "Could not open the luks mapping: %s" % (errout.strip(), )
+			self.log.warn(errorMsg)
+			raise CBMountError(errorMsg)
+		proc = subprocess.Popen(
+			shell = False,
+			stdin = None,
+			stdout = devnull,
+			stderr = subprocess.PIPE,
+			args = [
+				self.cbox.prefs["Programs"]["super"],
+				self.cbox.prefs["Programs"]["CryptoBoxRootActions"],
+				"mount",
+				os.path.join(self.__dmDir, self.name),
+				self.__getMountPoint()])
+		proc.wait()
+		if proc.returncode != 0:
+			errorMsg = "Could not mount the filesystem: %s" % (proc.stderr.read().strip(), )
+			self.log.warn(errorMsg)
+			raise CBMountError(errorMsg)
+		devnull.close()
+
+
+	def __umountLuks(self):
+		"umount a luks partition"
+		devnull = None
+		try:
+			devnull = open(os.devnull, "w")
+		except IOError:
+			self.log.warn("Could not open %s" % (os.devnull, ))
+		if self.isMounted():
+			proc = subprocess.Popen(
+				shell = False,
+				stdin = None,
+				stdout = devnull,
+				stderr = subprocess.PIPE,
+				args = [
+					self.cbox.prefs["Programs"]["super"],
+					self.cbox.prefs["Programs"]["CryptoBoxRootActions"],
+					"umount",
+					self.__getMountPoint()])
+			proc.wait()
+			if proc.returncode != 0:
+				errorMsg = "Could not umount the filesystem: %s" % (proc.stderr.read().strip(), )
+				self.log.warn(errorMsg)
+				raise CBUmountError(errorMsg)
+		if os.path.exists(os.path.join(self.__dmDir, self.name)):
+			proc = subprocess.Popen(
+				shell = False,
+				stdin = None,
+				stdout = devnull,
+				stderr = subprocess.PIPE,
+				args = [
+					self.cbox.prefs["Programs"]["super"],
+					self.cbox.prefs["Programs"]["CryptoBoxRootActions"],
+					"cryptsetup",
+					"luksClose",
+					self.name,
+					"--batch-mode"])
+			proc.wait()
+			if proc.returncode != 0:
+				errorMsg = "Could not remove the luks mapping: %s" % (proc.stderr.read().strip(), )
+				self.log.warn(errorMsg)
+				raise CBUmountError(errorMsg)
+		devnull.close()
+
+
+	def __mountPlain(self):
+		"mount a plaintext partition"
+		if self.isMounted(): raise CBVolumeIsActive("this container is already active")
+		devnull = None
+		try:
+			devnull = open(os.devnull, "w")
+		except IOError:
+			self.log.warn("Could not open %s" % (os.devnull, ))
+		self.__cleanMountDirs()
+		if not os.path.exists(self.__getMountPoint()):
+			os.mkdir(self.__getMountPoint())
+		if not os.path.exists(self.__getMountPoint()):
+			errorMsg = "Could not create mountpoint (%s)" % (self.__getMountPoint(), )
+			self.log.error(errorMsg)
+			raise CBMountError(errorMsg)
+		proc = subprocess.Popen(
+			shell = False,
+			stdin = None,
+			stdout = devnull,
+			stderr = subprocess.PIPE,
+			args = [
+				self.cbox.prefs["Programs"]["super"],
+				self.cbox.prefs["Programs"]["CryptoBoxRootActions"],
+				"mount",
+				self.device,
+				self.__getMountPoint()])
+		proc.wait()
+		if proc.returncode != 0:
+			errorMsg = "Could not mount the filesystem: %s" % (proc.stderr.read().strip(), )
+			self.log.warn(errorMsg)
+			raise CBMountError(errorMsg)
+		devnull.close()
+
+
+	def __umountPlain(self):
+		"umount a plaintext partition"
+		devnull = None
+		try:
+			devnull = open(os.devnull, "w")
+		except IOError:
+			self.log.warn("Could not open %s" % (os.devnull, ))
+		if self.isMounted():
+			proc = subprocess.Popen(
+				shell = False,
+				stdin = None,
+				stdout = devnull,
+				stderr = subprocess.PIPE,
+				args = [
+					self.cbox.prefs["Programs"]["super"],
+					self.cbox.prefs["Programs"]["CryptoBoxRootActions"],
+					"umount",
+					self.__getMountPoint()])
+			proc.wait()
+			if proc.returncode != 0:
+				errorMsg = "Could not umount the filesystem: %s" % (proc.stderr.read().strip(), )
+				self.log.warn(errorMsg)
+				raise CBUmountError(errorMsg)
+		devnull.close()
+	
+
+	def __createPlain(self):
+		"make a plaintext partition"
+		if self.isMounted():
+			raise CBVolumeIsActive("deactivate the partition before filesystem initialization")
+		devnull = None
+		try:
+			devnull = open(os.devnull, "w")
+		except IOError:
+			self.log.warn("Could not open %s" % (os.devnull, ))
+		proc = subprocess.Popen(
+			shell = False,
+			stdin = None,
+			stdout = devnull,
+			stderr = subprocess.PIPE,
+			args = [
+				self.cbox.prefs["Programs"]["mkfs-data"],
+				self.device])
+		proc.wait()
+		if proc.returncode != 0:
+			errorMsg = "Could not create the filesystem: %s" % (proc.stderr.read().strip(), )
+			self.log.error(errorMsg)
+			raise CBCreateError(errorMsg)
+		devnull.close()
+
+
+	def __createLuks(self, password):
+		"make a luks partition"
+		if not password:
+			raise CBInvalidPassword("no password supplied for new luks mapping")
+		if self.isMounted():
+			raise CBVolumeIsActive("deactivate the partition before filesystem initialization")
+		devnull = None
+		try:
+			devnull = open(os.devnull, "w")
+		except IOError:
+			self.log.warn("Could not open %s" % (os.devnull, ))
+		"remove any potential open luks mapping"
+		self.__umountLuks()
+		"create the luks header"
+		proc = subprocess.Popen(
+			shell = False,
+			stdin = subprocess.PIPE,
+			stdout = devnull,
+			stderr = subprocess.PIPE,
+			args = [
+				self.cbox.prefs["Programs"]["super"],
+				self.cbox.prefs["Programs"]["CryptoBoxRootActions"],
+				"cryptsetup",
+				"luksFormat",
+				self.device,
+				"--batch-mode",
+				"--cipher", self.cbox.prefs["Main"]["DefaultCipher"],
+				"--iter-time", "2000"])
+		proc.stdin.write(password)
+		(output, errout) = proc.communicate()
+		if proc.returncode != 0:
+			errorMsg = "Could not create the luks header: %s" % (errout.strip(), )
+			self.log.error(errorMsg)
+			raise CBCreateError(errorMsg)
+		"open the luks container for mkfs"
+		proc = subprocess.Popen(
+			shell = False,
+			stdin = subprocess.PIPE,
+			stdout = devnull,
+			stderr = subprocess.PIPE,
+			args = [
+				self.cbox.prefs["Programs"]["super"],
+				self.cbox.prefs["Programs"]["CryptoBoxRootActions"],
+				"cryptsetup",
+				"luksOpen",
+				self.device,
+				self.name,
+				"--batch-mode"])
+		proc.stdin.write(password)
+		(output, errout) = proc.communicate()
+		if proc.returncode != 0:
+			errorMsg = "Could not open the new luks mapping: %s" % (errout.strip(), )
+			self.log.error(errorMsg)
+			raise CBCreateError(errorMsg)
+		"make the filesystem"
+		proc = subprocess.Popen(
+			shell = False,
+			stdin = None,
+			stdout = devnull,
+			stderr = subprocess.PIPE,
+			args = [
+				self.cbox.prefs["Programs"]["mkfs-data"],
+				os.path.join(self.__dmDir, self.name)])
+		proc.wait()
+		"remove the mapping - for every exit status"
+		self.__umountLuks()
+		if proc.returncode != 0:
+			errorMsg = "Could not create the filesystem: %s" % (proc.stderr.read().strip(), )
+			self.log.error(errorMsg)
+			"remove the luks mapping"
+			raise CBCreateError(errorMsg)
+		devnull.close()
+
+
+	def __cleanMountDirs(self):
+		"""	remove all unnecessary subdirs of the mount parent directory
+			this should be called for every (u)mount	"""
+		subdirs = os.listdir(self.cbox.prefs["Locations"]["MountParentDir"])
+		for dir in subdirs:
+			abs_dir = os.path.join(self.cbox.prefs["Locations"]["MountParentDir"], dir)
+			if (not os.path.islink(abs_dir)) and os.path.isdir(abs_dir) and (not os.path.ismount(abs_dir)):
+				os.rmdir(abs_dir)
+
+

bin/CryptoBoxExceptions.py

@@ -0,0 +1,107 @@
+"""
+exceptions of the cryptobox package
+"""
+
+
+class CryptoBoxError(Exception):
+	"""base class for exceptions of the cryptobox"""
+	pass
+
+
+class CBConfigError(CryptoBoxError):
+	"""any kind of error related to the configuration of a cryptobox"""
+	pass
+
+
+class CBConfigUnavailableError(CBConfigError):
+	"""config file/input was not available at all"""
+	
+	def __init__(self, source=None):
+		self.source = source
+	
+	def __str__(self):
+		if self.source:
+			return "failed to access the configuration of the cryptobox: %s" % self.source
+		else:
+			return "failed to access the configuration of the cryptobox"
+
+
+class CBConfigUndefinedError(CBConfigError):
+	"""a specific configuration setting was not defined"""
+
+	def __init__(self, section, name=None):
+		self.section = section
+		self.name = name
+	
+	def __str__(self):
+		# is it a settings or a section?
+		if self.name:
+			# setting
+			return "undefined configuration setting: [%s]->%s - please check your configuration file" % (self.section, self.name)
+		else:
+			# section
+			return "undefined configuration section: [%s] - please check your configuration file" % (self.section, )
+			
+
+
+class CBConfigInvalidValueError(CBConfigError):
+	"""a configuration setting was invalid somehow"""
+
+	def __init__(self, section, name, value, reason):
+		self.section = section
+		self.name = name
+		self.value = value
+		self.reason = reason
+	
+	def __str__(self):
+		return "invalid configuration setting [%s]->%s (%s): %s" % (self.section, self.name, self.value, self.reason)
+
+
+class CBEnvironmentError(CryptoBoxError):
+	"""some part of the environment of the cryptobox is broken
+	e.g. the wrong version of a required program
+	"""
+
+	def __init__(self, desc):
+		self.desc = desc
+
+	def __str__(self):
+		return "misconfiguration detected: %s" % self.desc
+
+
+class CBContainerError(CryptoBoxError):
+	"""any error raised while manipulating a cryptobox container"""
+	
+	def __init__(self, desc):
+		self.desc = desc
+
+	def __str__(self):
+		return self.desc
+
+class CBCreateError(CBContainerError):
+	pass
+
+class CBVolumeIsActive(CBContainerError):
+	pass
+
+class CBInvalidName(CBContainerError):
+	pass
+
+class CBNameActivelyUsed(CBContainerError):
+	pass
+
+class CBInvalidType(CBContainerError):
+	pass
+
+class CBInvalidPassword(CBContainerError):
+	pass
+
+class CBChangePasswordError(CBContainerError):
+	pass
+
+class CBMountError(CBContainerError):
+	pass
+
+class CBUmountError(CBContainerError):
+	pass
+

bin/CryptoBoxPlugin.py

@@ -0,0 +1,165 @@
+# $Id$
+#
+# parent class for all plugins of the CryptoBox
+#
+
+import os
+import cherrypy
+
+
+class CryptoBoxPlugin:
+
+	## default capability is "system" - the other supported capability is: "volume"
+	pluginCapabilities = [ "system" ]
+
+	## does this plugin require admin authentification?
+	requestAuth = False
+
+	## is this plugin enabled by default?
+	enabled = True
+
+	## default rank (0..100) of the plugin in listings (lower value means higher priority)
+	rank = 80
+
+
+	## default icon of this plugin (relative path)
+	defaultIconFileName = "plugin_icon.png"
+
+
+	def __init__(self, cbox, pluginDir):
+		self.cbox = cbox
+		self.hdf = {}
+		self.pluginDir = pluginDir
+		self.hdf_prefix = "Data.Plugins.%s." % self.getName()
+
+
+	def doAction(self, **args):
+		"""override doAction with your plugin code"""
+		raise Exception, "undefined action handler ('doAction') in plugin '%'" % self.getName()
+	
+
+	def getStatus(self):
+		"""you should override this, to supply useful state information"""
+		raise Exception, "undefined state handler ('getStatus') in plugin '%'" % self.getName()
+	
+
+	def getName(self):
+		"""the name of the python file (module) should be the name of the plugin"""
+		return self.__module__
+	
+
+	@cherrypy.expose
+	def getIcon(self, image=None, **kargs):
+		"""return the image data of the icon of the plugin
+		
+		the parameter 'image' may be used for alternative image locations (relative
+		to the directory of the plugin)
+		'**kargs' is necessary, as a 'weblang' attribute may be specified (and ignored)"""
+		import cherrypy, re
+		if (image is None): # or (re.search(u'[\w-\.]', image)):
+			plugin_icon_file = os.path.join(self.pluginDir, self.defaultIconFileName)
+		else:
+			plugin_icon_file = os.path.join(self.pluginDir, image)
+		if not os.access(plugin_icon_file, os.R_OK):
+			plugin_icon_file = os.path.join(self.cbox.prefs["Locations"]["PluginDir"], "plugin_icon_unknown.png")
+		return cherrypy.lib.cptools.serveFile(plugin_icon_file)
+
+
+	def getTemplateFileName(self, template_name):
+		"""return the filename of the template, if it is part of this plugin
+
+		use this function to check, if the plugin provides the specified template
+		"""
+		result_file = os.path.join(self.pluginDir, template_name + ".cs")
+		if os.access(result_file, os.R_OK) and os.path.isfile(result_file):
+			return result_file
+		else:
+			return None
+
+
+	def getLanguageData(self, lang="en"):
+		try:
+			import neo_cgi, neo_util
+		except:
+			raise CryptoBoxExceptions.CBEnvironmentError("couldn't import 'neo_*'! Try 'apt-get install python-clearsilver'.")
+		langdir = os.path.abspath(os.path.join(self.pluginDir, "lang"))
+		## first: the default language file (english)
+		langFiles = [os.path.join(langdir, "en.hdf")]
+		## maybe we have to load a translation afterwards
+		if lang != "en":
+			langFiles.append(os.path.join(langdir, lang + ".hdf"))
+		file_found = False
+		lang_hdf = neo_util.HDF()
+		for langFile in langFiles:
+			if os.access(langFile, os.R_OK):
+				lang_hdf.readFile(langFile)
+				file_found = True
+		if file_found:
+			return lang_hdf
+		else:
+			self.cbox.log.debug("Couldn't find a valid plugin language file (%s)" % str(langFiles))
+			return None
+
+
+	def loadDataSet(self, hdf):
+		for (key, value) in self.hdf.items():
+			hdf.setValue(key, str(value))
+
+
+	def isAuthRequired(self):
+		"""check if this plugin requires authentication
+		first step: check plugin configuration
+		second step: check default value of plugin"""
+		try:
+			if self.cbox.prefs.pluginConf[self.getName()]["requestAuth"] is None:
+				return self.requestAuth
+			if self.cbox.prefs.pluginConf[self.getName()]["requestAuth"]:
+				return True
+			else:
+				return False
+		except KeyError:
+			return self.requestAuth
+
+
+	def isEnabled(self):
+		"""check if this plugin is enabled
+		first step: check plugin configuration
+		second step: check default value of plugin"""
+		import types
+		try:
+			if self.cbox.prefs.pluginConf[self.getName()]["enabled"] is None:
+				return self.enabled
+			if self.cbox.prefs.pluginConf[self.getName()]["enabled"]:
+				return True
+			else:
+				return False
+		except KeyError:
+			return self.enabled
+
+
+	def getRank(self):
+		"""check the rank of this plugin
+		first step: check plugin configuration
+		second step: check default value of plugin"""
+		try:
+			if self.cbox.prefs.pluginConf[self.getName()]["rank"] is None:
+				return self.rank
+			return int(self.cbox.prefs.pluginConf[self.getName()]["rank"])
+		except KeyError, TypeError:
+			return self.rank
+
+
+	def getTestClass(self):
+		import imp
+		pl_file = os.path.join(self.pluginDir, "unittests.py")
+		if os.access(pl_file, os.R_OK) and os.path.isfile(pl_file):
+			try:
+				return getattr(imp.load_source("unittests_%s" % self.getName(), pl_file), "unittests")
+			except AttributeError:
+				pass
+		try:
+			self.cbox.log.info("could not load unittests for plugin: %s" % self.getName())
+		except AttributeError:
+			pass
+		return None
+

bin/CryptoBoxRootActions.py

@@ -0,0 +1,386 @@
+#!/usr/bin/env python2.4
+
+"""module for executing the programs, that need root privileges
+
+Syntax:
+	- program
+	- device
+	- [action]
+	- [action args]
+
+this script will always return with an exitcode 0 (true), if "check" is the only argument
+"""
+
+import os
+import sys
+import subprocess
+import pwd
+import grp
+import types
+
+allowedProgs = {
+	"sfdisk":	"/sbin/sfdisk",
+	"cryptsetup":	"/sbin/cryptsetup",
+	"mount":	"/bin/mount",
+	"umount":	"/bin/umount",
+	"blkid":	"/sbin/blkid",
+	}
+
+
+DEV_TYPES = { "pipe":1, "char":2, "dir":4, "block":6, "file":8, "link":10, "socket":12}
+
+
+def checkIfPluginIsSafe(plugin):
+	"""check if the plugin and its parents are only writeable for root"""
+	#FIXME: for now we may skip this test - but users will not like it this way :)
+	return True
+	props = os.stat(plugin)
+	## check if it is owned by non-root
+	if props.st_uid != 0: return False
+	## check group-write permission if gid is not zero
+	if (props.st_gid != 0) and (props.st_mode % 32 / 16 > 0): return False
+	## check if it is world-writeable
+	if props.st_mode % 4 / 2 > 0: return False
+	## are we at root-level (directory-wise)? If yes, then we are ok ...
+	if plugin == os.path.sep: return True
+	## check if the parent directory is ok - recursively :)
+	return checkIfPluginIsSafe(os.path.dirname(os.path.abspath(plugin)))
+
+
+def	checkIfPluginIsValid(plugin):
+	import imp
+	try:
+		x = imp.load_source("cbox_plugin",plugin)
+	except Exception:
+		return False
+	try:
+		if getattr(x, "PLUGIN_TYPE") == "cryptobox":
+			return True
+		else:
+			return False
+	except Exception:
+		return False
+
+
+def call_plugin(args):
+	"""check if the plugin may be called - and do it finally ..."""
+	plugin = os.path.abspath(args[0])
+	del args[0]
+	## check existence and excutability
+	if not os.access(plugin, os.X_OK):
+		raise Exception, "could not find executable plugin (%s)" % plugin
+	## check if the plugin (and its parents) are only writeable for root
+	if not checkIfPluginIsSafe(plugin):
+		raise Exception, "the plugin (%s) was not safe - check its (and its parents') permissions" % plugin
+	## check if the plugin is a python program, that is marked as a cryptobox plugin
+	if not checkIfPluginIsValid(plugin):
+		raise Exception, "the plugin (%s) is not a correctly marked python script" % plugin
+	args.insert(0,plugin)
+	proc = subprocess.Popen(
+		shell = False,
+		args = args)
+	proc.wait()
+	return proc.returncode == 0
+
+
+def isWriteable(device, force_dev_type=None):
+	"""check if the calling user (not root!) has write access to the device/file
+
+	the real (not the effictive) user id is used for the check
+	additionally the permissions of the default groups of the real uid are checked
+	this check works nicely together with "super", as it changes (by default) only
+	the effective uid (not the real uid)
+	"""
+	# first check, if the device/file exists
+	if not os.path.exists(device):
+		return False
+	# check the type of the device - if necessary
+	if not force_dev_type is None:
+		dev_type = os.stat(device).st_mode % 65536 / 4096
+		if dev_type != force_dev_type: return False
+	# retrieve the information for the real user id
+	(trustUserName, trustUID, groupsOfTrustUser) = getUserInfo(os.getuid())
+	# set the default groups of the caller for the check (restore them later)
+	savedGroups = os.getgroups()
+	os.setgroups(groupsOfTrustUser)
+	# check permissions
+	result = os.access(device, os.W_OK) and os.access(device, os.R_OK)
+	# reset the groups of this process
+	os.setgroups(savedGroups)
+	return result
+
+
+def run_cryptsetup(args):
+	"""execute cryptsetup as root
+
+	@args: list of arguments - they will be treated accordingly to the first element
+		of this list (the action)"""
+	if not args: raise "WrongArguments", "no action for cryptsetup supplied"
+	if type(args) != types.ListType: raise "WrongArguments", "invalid arguments supplied: %s" % (args, )
+	try:
+		action = args[0]
+		del args[0]
+		device = None
+		cmd_args = []
+		if action == "luksFormat":
+			device = args[0]; del args[0]
+			cmd_args.append(action)
+			cmd_args.append(device)
+		elif action == "luksUUID":
+			device = args[0]; del args[0]
+			cmd_args.append(action)
+			cmd_args.append(device)
+		elif action == "luksOpen":
+			if len(args) < 2: raise "WrongArguments", "missing arguments"
+			device = args[0]; del args[0]
+			destination = args[0]; del args[0]
+			cmd_args.append(action)
+			cmd_args.append(device)
+			cmd_args.append(destination)
+		elif action == "luksClose":
+			if len(args) < 1: raise "WrongArguments", "missing arguments"
+			destination = args[0]; del args[0]
+			# maybe add a check for the mapped device's permissions?
+			# dmsetup deps self.device
+			cmd_args.append(action)
+			cmd_args.append(destination)
+		elif action == "luksAddKey":
+			device = args[0]; del args[0]
+			cmd_args.append(action)
+			cmd_args.append(device)
+		elif action == "luksDelKey":
+			if len(cs_args) < 2: raise "WrongArguments", "missing arguments"
+			device = args[0]; del args[0]
+			cmd_args.insert(-1, action)
+			cmd_args.insert(-1, device)
+		elif action == "isLuks":
+			device = args[0]; del args[0]
+			cmd_args.append(action)
+			cmd_args.append(device)
+		else: raise "WrongArguments", "invalid action supplied: %s" % (action, )
+		# check if a device was defined - and check it
+		if (not device is None) and (not isWriteable(device, DEV_TYPES["block"])):
+			raise "WrongArguments", "%s is not a writeable block device" % (device, )
+		cs_args = [allowedProgs["cryptsetup"]]
+		cs_args.extend(args)
+		cs_args.extend(cmd_args)
+	except (TypeError, IndexError):
+		raise "WrongArguments", "invalid arguments supplied: %s" % (args, )
+	# execute cryptsetup with the given parameters
+	proc = subprocess.Popen(
+		shell = False,
+		args = cs_args)
+	proc.wait()
+	## chown the devmapper block device to the cryptobox user
+	if (proc.returncode == 0) and (action == "luksOpen"):
+		os.chown(os.path.join(os.path.sep, "dev", "mapper", destination), os.getuid(), os.getgid())
+	return proc.returncode == 0
+
+
+def run_sfdisk(args):
+	"""execute sfdisk for partitioning
+
+	not implemented yet"""
+	print "ok - you are free to call sfdisk ..."
+	print "  not yet implemented ..."
+	return True
+
+
+def getFSType(device):
+	"""get the filesystem type of a device"""
+	proc = subprocess.Popen(
+		shell = False,
+		stdout	= subprocess.PIPE,
+		args = [ allowedProgs["blkid"],
+			"-s", "TYPE",
+			"-o", "value",
+			"-c", os.devnull,
+			"-w", os.devnull,
+			device])
+	(stdout, stderr) = proc.communicate()
+	if proc.returncode != 0:
+		return None
+	return stdout.strip()
+
+
+def run_mount(args):
+	"""execute mount
+	"""
+	if not args: raise "WrongArguments", "no destination for mount supplied"
+	if type(args) != types.ListType: raise "WrongArguments", "invalid arguments supplied: %s" % (args, )
+	try:
+		device = args[0]
+		del args[0]
+		destination = args[0]
+		del args[0]
+		# check permissions for the device
+		if not isWriteable(device, DEV_TYPES["block"]):
+			raise "WrongArguments", "%s is not a writeable block device" % (device, )
+		## check permissions for the mountpoint
+		if not isWriteable(destination, DEV_TYPES["dir"]):
+			raise "WrongArguments", "the mountpoint (%s) is not writeable" % (destination, )
+		# check for additional (not allowed) arguments
+		if len(args) != 0:
+			raise "WrongArguments", "too many arguments for 'mount': %s" % (args, )
+	except TypeError:
+		raise "WrongArguments", "invalid arguments supplied: %s" % (args, )
+	# execute mount with the given parameters
+	# first overwrite the real uid, as 'mount' wants this to be zero (root)
+	savedUID = os.getuid()
+	os.setuid(os.geteuid())
+	## we have to change the permissions of the mounted directory - otherwise it will
+	## not be writeable for the cryptobox user
+	## for 'vfat' we have to do this during mount
+	## for ext2/3 we have to do it afterward
+	## first: get the user/group of the target
+	(trustUserName, trustUID, groupsOfTrustUser) = getUserInfo(savedUID)
+	trustGID = groupsOfTrustUser[0]
+	fsType = getFSType(device)
+	## define arguments
+	if fsType == "vfat":
+		## add the "uid/gid" arguments to the mount call
+		mount_args = [allowedProgs["mount"],
+			"-o", "uid=%d,gid=%d" % (trustUID, trustGID),
+			device,
+			destination]
+	else:
+		## all other filesystem types will be handled after mount
+		mount_args = [allowedProgs["mount"], device, destination]
+	# execute mount
+	proc = subprocess.Popen(
+		shell = False,
+		args = mount_args)
+	proc.wait()
+	## return in case of an error
+	if proc.returncode != 0:
+		return False
+	## for vfat: we are done
+	if fsType == "vfat": return True
+	## for all other filesystem types: chown the mount directory
+	try:
+		os.chown(destination, trustUID, groupsOfTrustUser[0])
+	except OSError, errMsg:
+		sys.stderr.write("could not chown the mount destination (%s) to the specified user (%d/%d): %s\n" % (destination, trustUID, groupsOfTrustUser[0], errMsg))
+		sys.stderr.write("UID: %d\n" % (os.geteuid(),))
+		return False
+	## BEWARE: it would be nice, if we could restore the previous uid (not euid) but
+	## this would also override the euid (see 'man 2 setuid') - any ideas?
+	return True
+
+
+def run_umount(args):
+	"""execute mount
+	"""
+	if not args: raise "WrongArguments", "no mountpoint for umount supplied"
+	if type(args) != types.ListType: raise "WrongArguments", "invalid arguments supplied"
+	try:
+		destination = args[0]
+		del args[0]
+		# check permissions for the destination
+		if not isWriteable(os.path.dirname(destination), DEV_TYPES["dir"]):
+			raise "WrongArguments", "the parent of the mountpoint (%s) is not writeable" % (destination, )
+		if len(args) != 0: raise "WrongArguments", "umount does not allow arguments"
+	except TypeError: