#============================================================================ # This library is free software; you can redistribute it and/or # modify it under the terms of version 2.1 of the GNU Lesser General Public # License as published by the Free Software Foundation. # # This library is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU # Lesser General Public License for more details. # # You should have received a copy of the GNU Lesser General Public # License along with this library; if not, write to the Free Software # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA #============================================================================ # Copyright (C) 2004, 2005 Mike Wray # Copyright (C) 2005, 2006 XenSource Inc. #============================================================================ import re import string import os from xen.util import blkif import xen.util.xsm.xsm as security from xen.xend.XendError import VmError from xen.xend.server.DevController import DevController from xen.util import xsconstants, auxbin class BlkifController(DevController): """Block device interface controller. Handles all block devices for a domain. """ def __init__(self, vm): """Create a block device controller. """ DevController.__init__(self, vm) def _isValidProtocol(self, protocol): if protocol in ('phy', 'file', 'tap'): return True return os.access(auxbin.scripts_dir() + '/block-%s' % protocol, os.X_OK) def getDeviceDetails(self, config): """@see DevController.getDeviceDetails""" uname = config.get('uname', '') dev = config.get('dev', '') if 'ioemu:' in dev: (_, dev) = string.split(dev, ':', 1) try: (dev, dev_type) = string.split(dev, ':', 1) except ValueError: dev_type = "disk" if not uname: if dev_type == 'cdrom': (typ, params) = ("", "") else: raise VmError( 'Block device must have physical details specified') else: try: (typ, params) = string.split(uname, ':', 1) if not self._isValidProtocol(typ): raise VmError('Block device type "%s" is invalid.' % typ) except ValueError: raise VmError( 'Block device must have physical details specified') mode = config.get('mode', 'r') if mode not in ('r', 'w', 'w!'): raise VmError('Invalid mode') back = {'dev' : dev, 'type' : typ, 'params' : params, 'mode' : mode, } uuid = config.get('uuid') if uuid: back['uuid'] = uuid bootable = config.get('bootable', None) if bootable != None: back['bootable'] = str(bootable) if security.on() == xsconstants.XS_POLICY_USE: self.do_access_control(config, uname) (device_path, devid) = blkif.blkdev_name_to_number(dev) if devid is None: raise VmError('Unable to find number for device (%s)' % (dev)) front = { device_path : "%i" % devid, 'device-type' : dev_type } protocol = config.get('protocol') if protocol: front['protocol'] = protocol return (devid, back, front) def do_access_control(self, config, uname): (label, ssidref, policy) = \ security.get_res_security_details(uname) domain_label = self.vm.get_security_label() if domain_label: rc = security.res_security_check_xapi(label, ssidref, policy, domain_label) if rc == 0: raise VmError("VM's access to block device '%s' denied" % uname) else: from xen.util.acmpolicy import ACM_LABEL_UNLABELED if label != ACM_LABEL_UNLABELED: raise VmError("VM must have a security label to access " "block device '%s'" % uname) def reconfigureDevice(self, _, config): """@see DevController.reconfigureDevice""" (devid, new_back, new_front) = self.getDeviceDetails(config) (dev, mode) = self.readBackend(devid, 'dev', 'mode') dev_type = self.readFrontend(devid, 'device-type') if (dev_type == 'cdrom' and new_front['device-type'] == 'cdrom' and dev == new_back['dev'] and mode == 'r'): # dummy device self.writeBackend(devid, 'type', new_back['type'], 'params', '') # new backend-device self.writeBackend(devid, 'type', new_back['type'], 'params', new_back['params']) return new_back.get('uuid') else: raise VmError('Refusing to reconfigure device %s:%d to %s' % (self.deviceClass, devid, config)) def getDeviceConfiguration(self, devid, transaction = None): """Returns the configuration of a device. @note: Similar to L{configuration} except it returns a dict. @return: dict """ config = DevController.getDeviceConfiguration(self, devid, transaction) if transaction is None: devinfo = self.readBackend(devid, 'dev', 'type', 'params', 'mode', 'uuid', 'bootable') else: devinfo = self.readBackendTxn(transaction, devid, 'dev', 'type', 'params', 'mode', 'uuid', 'bootable') dev, typ, params, mode, uuid, bootable = devinfo if dev: if transaction is None: dev_type = self.readFrontend(devid, 'device-type') else: dev_type = self.readFrontendTxn(transaction, devid, 'device-type') if dev_type: dev += ':' + dev_type config['dev'] = dev if typ and params: config['uname'] = typ +':' + params else: config['uname'] = None if mode: config['mode'] = mode if uuid: config['uuid'] = uuid if bootable != None: config['bootable'] = int(bootable) proto = self.readFrontend(devid, 'protocol') if proto: config['protocol'] = proto return config def destroyDevice(self, devid, force): """@see DevController.destroyDevice""" # vbd device IDs can be either string or integer. Further, the # following string values are possible: # - devicetype/deviceid (vbd/51728) # - devicetype/devicename (/dev/xvdb) # - devicename (xvdb) # Let our superclass handle integer or devicetype/deviceid forms. # If we are given a device name form, then look up the device ID # from it, and destroy that ID instead. try: DevController.destroyDevice(self, devid, force) except ValueError: dev = self.convertToDeviceNumber(devid) for i in self.deviceIDs(): if i == dev: DevController.destroyDevice(self, i, force) return raise VmError("Device %s not connected" % devid) def convertToDeviceNumber(self, devid): try: dev = int(devid) except ValueError: if type(devid) is not str: raise VmError("devid %s is wrong type" % str(devid)) try: dev = devid.split('/')[-1] dev = int(dev) except ValueError: (device_path, dev) = blkif.blkdev_name_to_number(dev) return dev